Google will never touch it with a hundred-foot pole due to antitrust concerns, they're effectively banned from making any significant, user-experience-affecting changes to Chrome at this point.
Many people would immediately switch to a browser with 1) reliable Youtube ad blocking, 2) no cookie modals, and possibly 3) no other "distractors", like subscription pop-ups or "related articles" widgets.
Yes, ad blockers and reader mode can sort-of do all three, mostly, ish, but they're not easy to set up for non-techies, particularly on smartphones, even more particularly on iPhones, so a simple marketing pitch of "get this app, have these features" would probably work.
One would have to default to accepting cookies, though. Most users don't care either way, while website owners do. If you defaulted to refusing, they'd try to fight you and make their popups harder to auto dismiss, while auto-accepting would do the opposite.