Historically we’ve been quite hesitant to “mess with” existing sites, as it was very hard to tell whether admins had turned things off intentionally or they are just keeping the default because they weren’t aware of it. Changing defaults also used to be a bit painful from a rollout perspective.
Now, with upcoming changes, it becomes far easier to do these kind of rollouts in a low-risk way where admins are easily informed of the changes before they occur, and still have the opportunity to opt out of these features.