I believe the point was that it didn't fit the setting for the main characters of a typical fantasy plot—not being well-suited to traveling significant distances in rough terrain, among other things—not that they wouldn't have the basic tech. You don't see many active-duty soldiers or mercenaries fighting in wheelchairs and it seems likely the same considerations would apply to adventurers. You can come up with settings where it isn't totally implausible, but it will require some careful thought and ingenuity.