A recent article in Gizmodo/io9 argues that science fiction is very anti-handicapped. "What's with all the stairs?"
Weirdly, the article assumes that mobility-impaired people will still be using wheelchairs in the future rather than anti-grav technology. The author also embraces a "mobility impairment is natural" argument, in which advanced medicine's ability to correct genetically-caused mobility problems or to correct injury is rejected in favor of "embracing" one's "natural immobility". I'm not sure that most non-impaired people will agree with that, and that argument seems controversial even in the mobility-impaired movement. But that's not the argument I want to get into here.
The article made me wonder, and so I dug a bit. Stairs, ledges projecting upward in doorways, and the like are super-common in science fiction. Oddly, the depiction of mobility-impaired people is not! For a genre that proclaims itself wedded to diversity, almost no one in science fiction is shown to have lost the use of one or both legs or to have come from a low-gravity world (compared to Earth-normal gravity, the common standard seen in sci fi).
I looked and looked and looked, and only Farscape and the Star Trek franchise have depicted mobility impaired people. Star Trek really did so on The Next Generation, which had several episodes in which mobility-impaired people were depicted. Deep Space Nine went even further, devoting a whole episode to the problems faced by a person from a low-gravity world.
Why were wheelchairs depicted in these episodes, however? Star Trek is full of anti-grav; in fact, it seems to be used regularly! The fact is, time constraints (almost all depictions are in television series) and budget considerations force Trek into using wheelchairs rather than lift belts, anti-grav chairs, exoskeletons, or other technology. So let's take a look at what Trek has done.
A Starfleet officer attends a party in a wheelchair in the Discovery episode "Magic to Make the Sanest Man Go Mad" (season 1, ep. 7). The actual nature of this device is unclear. Is it a lifting chair (used to get the person upright)? A wheelchair-like device? Is it anti-grav, or not? We don't know, as the device is not seen in use.
Mobility-impaired people or wheelchairs are not depicted on Star Trek: Voyager, but we see someone use a wheelchair in Star Trek: Enterprise. Emory Erickson, the scientist who invents the transporter, visits the Enterprise in a wheelchair in the episode "Daedalus" (season 4, ep. 10). Once more, the transporter transporter pad is depicted with steps How did he get down? They certainly didn't beam him onto the floor.
Continuity-wise, the next time a wheelchair is seen is in the movie Star Trek (2009). Captain Pike is injured and is seen using one at the end of the film. Once more, it's a standard wheelchair, with no anti-grav ability.
The first time anti-grav is depicted in Star Trek is in the two-parter "The Menagerie" (season 1, ep. 11 and 12). Captain Christopher Pike is depicted using an anti-grav chair. Although the chair is never seen actually lifting off the ground, dialogue in the show specifically says it is an anti-grav chair. The prop was a motorized wheelchair with a black casing surrounding it. Actor Sean Kenney, who played the disabled Pike, could move the chair about himself and flash the lights on its front.
The second time anti-grav is seen in Star Trek was in the episode "The Changeling" (season 2, ep. 3). This is the first time we see anti-grav "handles" in use. These devices can attach themselves to any surface, and the projecting handles are grabbed by crew members and manipulated to provide lifting power. Two of these are seen here.
The anti-grav handles appear again in the TOS episode "Obsession" (season 2, ep. 18). Weirdly, there are actually messages on this device that indicate it can only lift up to 57 kg.
The lifting handles are seen again in the TOS episode "Is There in Truth No Beauty?" (season 3, ep. 5), another anti-grav device is depicted.
A truly outstanding use of anti-grav is seen in the TOS episode "The Cloud Minders" (season 3, ep. 21). Here, an entire city is suspended in the clouds!
Anti-gravity is seen in use multiple times in Star Trek: The Motion Picture Very casually, the use of an anti-grav vehicle is seen in use in the cargo bay before the Enterprise leaves space-dock. Below it, people are seen walking around without being affected by the anti-grav in use. As Kirk walks through the ship, a crewman passes by with an anti-grav sled in use. This is one of the few times where anti-grav is shown in use at waist-level, rather than low to the floor.
A kind of mobility-impairment device was seen in the film Star Trek V: The Final Frontier. Here, Spock is seen wearing rocket-powered boots. It's a completely insane idea. Where's the propellant coming from???? Ah well...
The first time a wheelchair-using individual is seen on TNG occurs quite early, in the episode "Too Short a Season" (season 1, ep. 16). Here, Admiral Mark Jameson is crippled by old age, and must use an anti-grav wheelchair. This episode notably shows the transporter pad being up a very short flight of three or four steps, just like in TOS. Jameson is not beamed directly onto the floor of the transporter room. He's beamed onto the pad itself. How did they get him down? Did he fly down? Was he bumped down the steps like a wheelchair? Did they re-beam him somewhere? The prop people really dislike the Jameson chair. It was huge, clunky, and hard to move around. It didn't take corners well, and at times could tip over.
Anti-grav sled from the TNG episode "The Enemy". Anti-grav sleds first appeared in the TNG episode "Time Squared" (season 2, ep. 13). They would appear a lot in TNG: "The Bonding" (season 3, ep. 5), "The Enemy" (season 3, ep. 7), "Power Play" (season 5, ep. 15), and "Schisms" (season 6, ep. 5). They'd show up in the DSN episodes "Past Prologue" (season 1, ep. 3), "The Nagus" (season 1, ep. 11), "Necessary Evil" (season 2, ep. 8), and "Family Business" (season 3, ep. 23). One would even be seen briefly in "Star Trek: Generations" when the medical team rushes to Geordi's aid after he's beamed back aboard the Enterprise from the Klingon ship.
Anti-grav sled from the TNG episode "Hollow Pursuits" (season 3, ep. 1). A whole episode was constructed around the failure of this sled. Because this sled differs from the one seen many times earlier (and later), I guess we have to assume there are two kinds of anti-grav lift/sleds in use. One appears to be for industrial use, the other for human beings and more delicate operations.
The DSN episode "Melora" (season 2, ep. 6) marks the first time that Star Trek directly engages a mobility-impaired person's needs. The TNG episode "Ethics" (season 5, ep. 16) had previously confronted the issue of mobility-impairment by having Worf become paralyzed. As a Klingon, he demands suicide. A physician proposes that she grow Worf a new spine using "genetronic" technology. But it's untested, and Worf could die. In the end, Worf is fine -- as we knew he'd be. (No show kills off a major cast member.)
"Melora", however, was different. The writer was himself a wheelchair user, and depicted the issues faced by such individuals by crafting a script about a person from a low-gravity world. Initially, the prop team wanted to use Admiral Jameson's old anti-grav chair. The DSN sets, however, had been designed with narrow corridors and smaller rooms as a cost-saving measure and to depict life on a cramped space station. The old prop proved too big! So the writer had to insert a line into the script in which someone says "Starfleet anti-grav technology won't work on a Cardassian space station." That seems ludicrous on the face of it, but oh well. A standard wheelchair was then modified to look "futuristic".
Somehow, the idea of the challenges a mobility impaired person would confront still had to be incorporated into the episode. Originally, the set's own dysfunction was to be made an issue. There was a script draft in which Melora (the low-grav off-worlder) wheels into Command; Capt. Sisko must then descend from his office down the stairs to greet her. Sisko was to feel uncomfortable and embarrassed at having to do so, which makes it look as if people have to condescendingly "descend to her level". That was jettisoned. Instead, Melora complains about corners, projecting ledges in doorways, and the like. It's more subtle, but I think it misses the point.