>bunkerchan is the leftist gab tbh
It's like Twitter but the source code is free to copypaste so you can host your own instance and don't need to program it yourself, all instances can by default interact with each other. However instance admins will typically block certain instances considered abusive. Gab is actually based off Mastodon code now, they weren't originally but they decided to convert to it. The guys behind Gab in part decided to convert to Mastodon code to try and troll the Mastodon creators and users who tended to be far to the left of Gab creators and users. Guy who programs Mastodon just kinda shrugged and blocked Gab from interacting with the main instance (mastodon.social I think). As well as other variously abusive instances. Most Mastodon instances as far as I know trend leftward. Especially radically leftward. There is a lot of variance between instances. I'm aware of there being instances targeted towards demographics of conservatives/fascists (Gab more or less), liberals/leftists/whatever, TERFs, LGBT-oriented instances, programming-oriented instances, anprim instances (yes I saw one or two of these while perusing), instances for particular languages (If you watch the "federated timeline", as opposed to the instance timeline or people-you-follow feed, on the instance you have an account for, it'll show posts from every single instance not blocked by the instance admin. You'll probably see some Japanese posts sprinkled around because there's Japanese-oriented instances), anarchist instances, etc. etc.
There's a lot there. Think of it like Twitter but more Discord-like in that you can make your own server if you like and customize it to however you want it to be. Except there is more freedom in Mastodon than in Discord, minus the fact you actually need to get a hold of the resources to host yourself. It is free/open source software.
Now as for dlive I don't know, but PeerTube may be worth checking out. As it happens, PeerTube is also
built on Mastodon.