Cure wounds could easily be interpreted as
It could far easier be interpreted as healing what the caster or their god perceives to be a wound, since IT'S THEM THAT DOES THE DAMN CURING.
I get inclusion, I really do. And if you wanna go there, the guy playing the cleric is a prick if he's doing this to a disabled guy's character. But you're not escaping this with logic, because disabled guy is also a prick.
You're in a universe of immortal gods, magic, amazing tech and telling stories. Don't you dare pretend there's any ailment that can't be healed by some random cleric of Waukeen or Kol Korran, both being deities of wealth that would approve of their priests being basically traveling salesmen, exchanging healing for money. You can cure anything for the right amount of gold, and let's not all act like we wouldn't want our walking/eyesight/hearing/whatever restored, and actively work to pay for one of these services.
Some of the traits we want to give our characters just don't translate into this magical world, and there's no ruling where a DM can still have it make sense if the cleric is in character when doing this. What you want to ask yourself before you get to this situation is, would this guy have seriously been crippled all his life and was never able to raise the few hundred gold for a healing spell? And would an adventuring party even want him on?
This should've been nixed at session 0 if not all players agree that this setting allows for incurable disabilities/diseases. Cause I for sure don't want a cleric in my party that "isn't allowed" to remove curses or heal. Oh, he's wheelchair-bound? The party exits the pub, you are unable to catch up to them as there are some stairs in the way. This is life without wheelchair ramps, better get used to some boring sessions ahead. Unless you wanna explore a dungeon and see if falling down stairs while stuck in a chair is gonna be easy to survive for your lvl1 wizard.
There are many reasons for why some teachers do some things.
We should not forget that one of them is "because they're useless cunts who have no idea what they're doing and they're just powertripping their way through some kids' education until the next paycheck".