That is very shortsighted. Just because “its twitter and microblogging” doesn’t mean it doesn’t affect someone on lemmy that doesn’t have it - people from mastodon can still read and reply to your comments there. Furthermore you yourself are on kbin that has an even larger integration with mastodon and other microblogging platforms, magazines themselves can be configured with specific tags so you get automatic engagement from other parts of the fediverse that aren’t on either lemmy or kbin.

And this is just ignoring the simple basic truth that it still affects other people that you are interacting with. Just because you don’t care doesn’t mean others don’t care, and if they leave, or want federation, or switch platforms, it affects your feed too.