Woah, this seems like a big jump to a form of technocracy / paternalism that I would think would typically require more justification than spending a short amount of time brainstorming in a comment thread why the thing millions of people use daily is actually bad.
Like, banning sites from offering free services if a character limit is involved because high status members of communities you like enjoy such sites seems like bad policy and also a weird way to try and convince these people to write on forums you prefer. Now, one counterargument would be "coordination problems" mean those writers would prefer to write somewhere else. But presumably if anyone's aware of "inadequate equilibria" like this and able to avoid it it would be Eliezer.
Re-reading my comment, I realize it may come off as snarky but I'm not really sure how better to convey my surprise that this would be the first idea that comes to mind.
ETA: it's not clear to me that Twitter is so toxic, especially for people in the broad bubble that encompasses LW / EA / tech / etc. I agree it's not the best possible version of a platform by any means, but to say it's obviously net negative seems like a stretch without further evidence.
If you want to explore the community more, I recommend reading the Library, checking recent Curated posts, seeing if there are any meetups in your area, and checking out the Getting Started section of the LessWrong FAQ.
The Open Thread sequence is here.