Genuinely don't understand this fixation to insert modern wheelchair designs into fantasy settings.

I'm not even opposed to the idea of a character with incurable paralysis in a fantasy setting. maybe healing magic is limited, maybe its a curse, I dont know
but there are scores of much more interesting ways they could mitigate the problem of their limited mobility in a fantasy context.

Plus the guy in a wheelchair is not going to be a fucking adventurer, thats for sure. the lich's undercroft is not wheelchair accessible. No ones gonna wanna maneuver a wheelchair amongst a bunch of loose piles of gold when raiding the dragon's lair.