If Twitter started doing no (or very little) moderation it would suddenly be in conflict with many laws around the globe including the EU and the US.
That did fly a few years ago but I doubt it does today.
Other shareholders might not be to thrilled about them being banned
Most platforms fail miserably at removing the former and just automate the latter. Twitter could spend a small fraction of their current moderation budget and still be in compliance with US law.
Of course Twitter is free to leave those markets at any time but I don't think other shareholders besides Musk would appreciate that.
Even in America, some brands were not that interested appearing next to fringe/extreme (though legal) content. And advertisers are the real customers of Twitter and all social media after all.
That's obviously true for authoritarian countries like China but even in "the West" there are competing definitions of what constitutes free speech.
If you want to operate in those countries (at scale) you need to localize your moderation policies and therefore "take a stance". Cost of doing business globally.
- banning
- shadow-banning
- deleting offensive messages
- detaching off-topic threads
The only difference with HN is that their rules are different. Everything else is very similar to Twitter.