Presumably the business/enterprise editions still do?

Enterprise might but Professional sure doesn't.

I just installed a copy of 25H2 on a laptop with a previously saved Professional licence.

You can just choose to create a "work or school account" and then leave the domain name empty.

Thanks!

I wonder how much of this is Microsoft trying to create recurring profits from the base (Home) sku, rather than that they care about local-user installations in any other circumstance.

Interesting, will give that a try next time. I guess I never looked because I had assumed that option made you connect to an existing domain.

I've used that workaround on literally dozens of installations in the last few years :)

Maybe not for the long term; business/enterprise are mostly using domain accounts for non-server systems.