Federation is managed at an instance level, by the administrators of that instance. Instances can take either an accept-list approach or a block-list approach. As an end user, you choose to de-federate from it by choosing an instance which de-federates from it (or by running your own instance). The moderation / personal block tools on Lemmy aren’t as sophisticated right now as they are on Mastodon, but ideally you should also be able to personally block instances from accessing your account as well.
A lot of third party communication occurs on the Fediverse though. If a community is hosted on server A, you come from server B, and another user comes from server C, it is reasonable to ask if server A will just hand server B’s content (replies, votes, etc.) to server C. On Mastodon, this is the default behavior, unless an instance enables the “Authorized Fetch” option. I am not sure how this works on Lemmy.
For the meantime though, Threads is focused on the microblogging format of social media, and compatibility with Mastodon in particular. Lemmy is probably less at risk. But you should still treat every public post like it is truly public. People run scrapers. People run bots. People can take snapshots on archive.org. Federated platforms are no different in this regard.
In general, I find the term “democratic socialism” to be pretty cringe. It’s like saying right up front “I’m not like those OTHER socialists!” Socialism is a liberatory project. Socialism is the auto-emancipation of the working class. THAT is what democracy looks like. Rule of the people.
Liberation comes hand in hand with revolution though. Socialism will certainly NOT be very democratic for the people who own vast amounts of real estate, productive machinery, and
propagandamedia empires. Those people will certainly need to end up on the wrong side of a gun for the project to succeed. The wise ones among them won’t force us to pull the trigger.It will be a hostile take-over. It will be a break from the constitutional order. It will be a break from the “rule of law.” When the ruling class starts losing the game, they will flip over the table. All your precious civil liberties will be torn to shreds. Fascism is simply capitalism under crisis.
The Liberals commit themselves to playing by the rules even when the fascists never would. Salvador Allende (the world’s first elected Marxist head of state) tried to do this, and in three years it ended in his death and a fascist military dictatorship. There is no room for idealism in revolution. The stakes are very real. You need to crush your enemies by any means necessary. Maybe you don’t give Rupert Murdoch the freedom of speech. Maybe you don’t respect Jeff Bezos’s property rights. Maybe you stuff all the Groypers into a mineshaft.
A lot of people whine about authoritarianism in the English speaking left, but the English-speaking left has no power to speak of. Just a bunch of very online sectarians bickering. We run around trying to cancel internet forums which amount to little more than fucking book clubs, as if they were the embodiment of high Stalinism.