It’s been seen time and time and time and time again and I’m not sure there’s any real way to preserve it.
You have a similar thing with tiny tourist places - everyone wanting to go there forces it to change, it cannot remain a tiny tourist place and almost always ends up being a place that is “on show”.
But in here, even the author seems to point to testimonials that indicate that value of unique discussions gained just by allowing the conversation to happen.
It is sad that it ended partially because author was harassed for hosting it, but I suppose this is the price you pay in 2022.
As it pertains to Musk and article linked to Musk, I am relatively certain he can handle the mob.
Tim Wu has a book "The Master Switch" also about this. I think his argument was once you become big enough, the rules change and you end up being forced to censor. You become valuable target for people who want censorship and close to a common carrier.