Yes, attestation is in line with V3 changes, just that it makes them irrelevant: YouTube’s website could some day ask for environment attestation of “no extension using the intercept hooks”, or “only the approved ones”, and still have the same effect. The fact that they’re implementing a server-side anti-adblock now, while postponing V2 deprecation over and over, makes me think the V3 changes are a flop.
Firefox… would likely require Mozilla to play ball and implement similar attestation in an official binary attestable by the OS. Edge too, just so MS doesn’t mess with Chrome’s binary attestation on Windows.
Safari already has attestation, without extra parameters, but it could be extended: