This policy has very little negative effects for disabled people. And if it does affect some then yes, that person might consider leaving as one option in response. The world doesn't revolve around you and when things change for the public good, you might have to adapt along with it. Why is this such a radical idea for you?

There is no "right to exist", and nobody can stop you from "existing", whatever that means. This is a nonsequiteur. A vague extremist statement thrown around to make things dramatic but is actually meaningless.

As for context, if you ignore it and just come in with a generic "what about the disabled people" in any possible conversation then there's no productive discussion to be had, which is clear in this case. You seem to be caught in an emotional argument against a position that was never made so I'll end it here.