Twitter is not purely a US forum. In some places the law may say that "hate speech" is illegal, or that politically dissident speech is illegal... what then? Are you presuming that US jurisprudence should be the standard for all of humanity, worldwide?
"We" is only "citizens of the USA". Other countries have quite a different tradition regarding this, and citizens of such countries often quite a different understanding than USA citizens of what is considered as "free speech" in the USA and what does not.
How do you avoid the problem of thousands of accounts from Russian-funded troll farms pumping out millions of disinformation tweets on everything from vaccine conspiracy theories, Ukraine wars, lies about elections and so on? Do you just accept that Putin gets a free ride to influence public opinion, destabilise the liberal democracies and nudge close elections in his favour?
Muting accounts might be good for my blood pressure (if I can mute thousands of accounts) but it doesn't fix problems like the above or interesting people getting bullied off the platform (it's bad enough already).
> No mora bans on so called "hate speech"
Why is hate speech "so-called" hate speech rather than just hate speech? Do you think Twitter would be a better forum if anyone can e.g. bombard a Black professor with racist abuse when they share some research?
Do you think HN would be better with no moderation?
> or politically dissident speech
This is not banned.