Who are you talking about? What the OP said was :

I don't have a problem with having disabled people in a TTRPG setting, but I hate the "it's fantasy, stop whining about realism" argument.

You came along, not to say anything about disabled people in RPGs, but to defend the claim "it's fantasy, stop whining about realism".

This isn't about disabilities, it's about dismissing any and all criticisms of fantasy simply because fantasy isn't the real world.

Fantasy, like any genre of fiction, is of course, made up, but that doesn't mean it doesn't have any rules. Each fantasy world establishes its own rules, and tries to follow it as best as it can, because that makes the worlds consistent, and more believable. Does that mean those rules can never be broken? No. But you need to come up with a reason why.

That's all this is about, coming up with reasons why things exist/happen, that's the core of fiction. If you have a reason why disabled people still exist in your games despite healing magic, that's awesome, keep at it. If you don't, i mean... You do you, but don't go complaining when people complain about it, they're not ableists (not necessarily at least), they just don't like bad writing.

You literally came up with a ton of reasons why disabled people can exist in a fantasy setting, so i don't understand why you're so against the idea.