The mute feature does what is required by those app stores. It allows you to remove the content you don't want to see from your feed and not receive correspondence from people you don't want to hear from.
The Twitter block feature is actually rather unique, as it currently exists. Social media platforms have ways to make it so you don't have to see or hear from other users of your choice. And most give users the ability to make posts private, so that only specific accounts can see it. Twitter is the only platform I'm aware of with a tool that lets you make it so only specific users can't see your posts. No app store requires social media apps to give users that ability. Youtube doesn't have that, nor does it have a feature named "block", it just has the ability to hide channels, and that obviously meets Google Play's terms.