We're all watching the first step of enshittification and thinking "this is fine"
I believe there is work around did web for an extension that would enable verifiable history
You can always create a new identity, I don't think anything has changed there. If you don't want your new identity connected to your old identity, then don't.
The right to be forgotten is whole separate problem. The only hope here, really, is that entropy takes care of it for you. I don't see how a chain of trust system can fundamentally be compatible with the right to be forgotten unless you relax the rules a bit.