One of the important features of Mastodon is that you can choose what your feed is. Everyone’s feed has an algorithm determining what’s in it even if it’s just a simple “list the posts of everyone I’ve subscribed to in chronological order.”
If someone else wants to see a feed of content that is curated and sorted in a different way, why get angry at them? They’re not forcing you to see that feed.
One thing that might be nice is if there could be a standard for user IDs that would allow multiple systems to work seamlessly together.
You could have Mastodon continue to focus solely on being a completely open media aggregator and social network, but also have some other completely independent and secure private messaging system that uses the same user ID system. Then if you want to send a private message to someone who’s made a Mastodon post you can use that and it “just works.”
Creating a universal user ID system that would work across all of this is challenging, of course.