ActivityPub in particular is radically public. It broadcasts what you post to a bunch of other servers run by anyone from IT professionals to kids, which could be anything from vanilla Mastodon running in a datacenter to an ad-hoc, informally-specified, bug-ridden slow implementation of half of ActivityPub running on a hacked smart toaster. It's for things you want to show to the world.

We have several good options for end-to-end encrypted communication, such as Matrix, which is open source and federated, or Signal, which several of my elderly relatives managed to figure out without coaching.

Right now, I can say "elon musk is a racist piece of shit who owes his entire life to his daddy's emerald mine that ran on apartheid". There is a slight chance that the dipshit cares enough to track me down and call me a pedophile but it is nigh zero.

I can also say how I feel about the CCP and Xinnie the Poo and putin and so forth with pretty minimal risk (my social credit score is already shit).

But what if I am actually a threat to a corporation because I am reporting on information that affects their bottom line? To the point that it is cheaper to pay some muscle to come rough me up. Suddenly, I am dependent on the platform caring more about their "image" than to cooperate.

Similarly, what if I am in a war torn country where roving bands of thugs are murdering anyone who gets in their way (... so possibly early 2025 US...)? Suddenly, that footage of a civilian being beheaded getting traced back to me is my life and the life of everyone I care about.

That is the scale we are talking about. Twitter was not a great company but they were, at least historically, good about not making it easy for those brutal regimes to get that information. That had already started to shift by the time musk took over but it is gone now.

And that, combined with active misinformation campaigns, is already defining the brutal conflict in Gaza.