Twitter and the Inability to be Polite
When you wish to correct someone, it would be impolite to do so in public.
Tweeting is like yelling into a crowded room. Great for self-promotion, but terrible for intimate conversations. You could DM, but that's not a part of the feed. It is outside of the normal user experience.
This is why birdsite is the way it is, and this is why privacy options and CWs are so important.