I don't know exactly what the "advanced flow" to install 'unverified' software is going to look like, but Google backtracking on requiring their approval to install apps on your phone is certainly a good thing to hear.
I'm sure they're going to make some sort of really inconvenient hoop to jump through, but I guess just about anything is better than outright preventing it.
As always, though, it's a good time to de-Google you're phone if that's something you'd be up to. It puts a nice little buffer in between you and Google's shenanigans. It's rather nice to be able to treat my phone as ... checks notes ... my phone.