I also think Bluesky is quite intolerant, but calling it Marxist is laughable - if anything, it's (socially) more like a Dem-leaning clone of X. That said, science/academia are special domains. These are pros who communicate on technical topics and are generally uninterested in engaging bots/trolls. As a result, more controlled environments (like Bluesky or LinkedIn) are naturally more appealing.

Personally, I followed the so-called "EnergyTwitter" for several years. It was (for myself) a remarkable phenomenon: a large community of engineers, scientists, and technicians sharing insights and ideas about energy, and I learned a lot from that. Unfortunately, it has largely dissipated now. Roughly half of that community has moved to Mastodon.energy, and the other half to Bsky.

The problem with X isn’t outright suppression, but rather manipulation of the recommender system, which is subtler. That’s another reason why having control over the client-side feed, as in Nostr, is so desirable.