>> "“Obscure Chromium forks” – like Samsung Internet and Edge?"

Yes, exactly like those two.

>> "Remember: Chromium itself is an “obscure fork” of WebKit..."

Actually when Google forked WebKit, Chrome wasn't obscure at all. But yes, that's the perfect proof that Google doesn't want to cooperate when they aren't pulling the strings.

Don't forget Opera is a re-skinned Chrome.

Right, at which point Opera too became completely irrelevant.

First they switched their engine to Blink, then predictably after 3 years sold out to an obscure Chinese private equity fund.

I mean it's re-skinned in the same way as Samsung Internet and I believe Edge will be: a totally different browser UI implementation around the same browser engine.

Samsung Internet has their own implementations of quite a few web standards - calling it a reskin isn’t very accurate