Mastodon getting some attention is actually pretty good. It's one of the first times in a while where an online social media network is largely free from corporate control. The code is free and open, and there's no algorithm pushing ads and PR - just a chronological feed of people you follow. And it's definitely more hospitable to leftists than Twitter is, since leftists will always be able to host servers and moderate them.
Hopefully more leftist servers come about, but in the meantime, you can find any server that has a decent description and rules and join that. I recommend sorting by uptime and open registration.
Regarding servers, I think the best one with signups available right now is kolektiva.social. I myself am on a bog-standard big server, and things there feel fine enough moderation-wise too. So don't worry too much about your choice, you can move your account pretty easily. Just find something that feels reliable to start off with.
Kolektiva seems pretty clearly anti-ML. I hate to say it but the best Twitter-like space for communists to speak, socialize, and propagandize is Twitter itself.
I think it is important to recognize that these are different things. If we want to agitate, we MUST go where the people are. There's no way around that. We must agitate on Twitter, Facebook, Reddit, TikTok, etc. On the other hand, if we want to hold conversations, casually debate tactics and rhetoric, and discuss history, theory, and current events in an environment where the conversation doesn't get derailed by Redditors and NAFO fascists, we NEED an alternative.
Our days are numbered on any monopoly social platform. The Department of Homeland Security is accelerating its propaganda operations with the specific goal of disorganizing leftist movements. They work directly with the corporate administration of these platforms. The Atlantic Council already participates in high level content moderation policy decisions on these platforms as well, and the CIA likely has a decent number of Reddit moderators who do this work in a clandestine fashion. It is their objective to categorize misinformation, disinformation, and "malinformation," and make it inaccessible to the masses.
Personally, Hexbear has served as a good alternative, but Hexbear is like a small clubhouse. The infrastructure required by anticapitalist movements across the board must be a lot more robust and expansive.
Glancing through their rules, it is a lot better than some other instances I've seen. I can't speak much on the membership or how the rules are applied in practice though. There are two things among them which stood out to me.
1: The thing about 'authoritarian' leftist movements and mass killings.
I mean yeah, if we're being sincere, this is nothing to look forward to or revel in. But it is hard to be sincere all the time, and you look at shit like RealPage where you have landlords across the country price fixing apartments driving people to homelessness and you can't help crack out the Mao jokes. Personally, I think I'd prefer an environment where these things can at least be entertained in jest, rather than an environment of self-censorship. Let the bourgeoisie at least be intimidated by the thought that we are entertaining these ideas.
2: The thing about Russian sources RE: the Russo-Ukranian war.
Again, if we are being sincere, we all know Putin is not a revolutionary. The war does have significant implications on the struggle against imperialism though. Truth is the first casualty of war. There is no straight reporting on either side of this thing. The best you can do is a sort of meta-analysis. See what stories each side is placing emphasis on, which stories each side is covering up. The last thing I want to see is everyone cheering on NATO and the Zelensky regime though because Russia took the initiative instead of allowing Ukraine to become fully integrated into the NATO alliance. While nothing compares to the idiocy of Reddit/Twitter NAFO freaks and the stupid liberals who still genuinely believe the US military is spreading democracy in the year 2022, the Russian nationalists are not free of cringe takes.
Personally, I'd reserve judgement until I'm familiar with how these rules are applied in practice. These are nuanced issues, at least. Even here, while we glorify the Maoist uprising against the landlords, people who embrace figures like Gonzalo uncritically tend to be treated with suspicion. Likewise, the war in Ukraine is a continuously developing situation. If they allow room for nuanced discussion, the quality of discussion is still probably miles better than most places on Twitter or Reddit. If they interpret these rules strictly, I agree many of us wouldn't last long.
Anyway, I'll peek around. I still might just end up being a trot and spinning up my own instance.
Also, it seems like their instance is struggling under load currently.