[aninhumer]

>saying "it once was A, now it's B, so it can never be A again" is exactly as "prescriptivist".

Except I'm not telling you what you can say, I'm telling you what other people do say, which is descriptivist. You can use meaning A if you want to, but don't expect people to understand you.

>You know, if all those other people say they just say it because "most" people do, then none of them actually do have a reason.

That's like saying no one in the US has a reason to speak English, they're doing it just because everyone else does.

Language is about shared understanding, so most people around you using a particular meaning is pretty much the only reason for someone to use it.

>you can call it progress

I don't call it progress, just change.