@sandwich nails it 

nostr:note1yzs6hc7yesc64ahajhv447s06rg9rc06xerfy8p24amw5xg9revqy3kkuv 

 the left depends on censoring their opponents to make their worldview consistent and to keep their sanity 

 Exactly. They can’t censor on #nostr 

 as does the mainstream right which is  far left of the proper radical right. 

 It's probably because Mastodon, and Bluesky have stronger network effects due to being around longer.

There's multiple factors really but I'd say that's a primary driver.

Nostr still has room to grow. 

 Liberal safe space. 

The concept that actual truth, logic, and reason might slip through without being censored. Is like a Vampire visiting an Italian restaurant and being offered garlic bread. They would burst into flames from a triggered rage if they consumed it at all.  

 Regular internet users don’t know that Nostr exists and onboarding on Bluesky is much easier. It’s working as expected of the category „social network“. Nostr is like Bitcoin in 2015. 

 I kinda feel upset about my favourite people going to bluesky instead of more progressive option..  

 I feel this about Bitcoin. That they are not interested in it. 

 nah it is different... btc is inevitable, nostr is optional 

 I quote a guy I follow on X after I asked him about nostr.. 

... honestly I just followed some people that I liked to the platform they went to - and then I liked what I saw and stayed :)
I'm sure there are other alternatives, too, but this one already seems "good enough" for me and has the people I'm interested in.