In terms of development effort, maintaining a browser fork that merely disables these features seems pretty easy. If you think users would prefer that, why not make one?
I personally don't think it would take off, because I think most user attitudes range from "want these features" to "ambivalence". But if you're so certain, why not try?
Why does it require a fork? Having an advanced settings page with checkboxes for each of these web features seems straightforward and not overly confusing to normal users.
This, I have Safari Debug Mode on purely to disable all the annoyance. And with the current state of things there will likely never be an extension to do that.
Maintaining a fork that does that isn’t trivial, but it’s certainly doable by any one engineer.
However, maintaining such a fork is not the only prerequisite for it “taking off”. It may well be that my great uncle would love that feature - but how are you going to get his attention when several vendors are already spending millions of dollars in marketing/design/etc to influence which browser he uses?
We hear this pretty often without any evidence. He is a user, you are a user, that makes two opinions.
I think the reality that companies set the rules and people just swallow what they get because alternatives require huge efforts.
We also heard that users want large tiles that are all over their desktop with zero functionality.