[1] https://developer.apple.com/app-store/review/guidelines/#use...
> To prevent abuse, apps with user-generated content or social networking services must include:
> A method for filtering objectionable material from being posted to the app
Filtering is exactly what muting does, which will still be allowed.
Even if that may be true, it seems X has been doing well lately. Admittedly, my timeline has been sharing a lot more interesting items than I had previously received.
Blocking will become a way to filter out responses you don't like, but others who follow you will still see comments and reactions if they also do not already have a user blocked.