A group of Telegram channels, I would say. Telegram is a vast network and is beautiful and obscene, because of the wide variety of channels it has, from pirates to anarchists to porno distributers to criminals to neo nazis. Some may disagree with such obscenity being beautiful, but I like the freedom as I am able to sift through it without being sucked in.
NoGoolag is an incredible one and also a starting point, though be warned, it has some anarchist minded and a tiny bit of conspiratorial news articles shared, but overall it is a goldmine. One can easily dive deep into resources from there, whoever is capable of not being sucked into the black hole.
One could get into establishing trust with the old ones and internet veterans (like myself) deep into Discord, IRC, Matrix, XMPP and darker corners. But I doubt most people, even here, can dive there and come out unaffected.
I am not sure of an answer here, really, that adds to the general answers already mentioned here, that might be safer to consume. But then I am the kind of person that loves to read, dig deep and investigate a lot, so that is just me.
Edit: if I may come off across as attacking anarchism, I do not mean that here. Some people really are just anti government absolutist nutjobs who preach anarchy to the next level. I am sure even actual anarchists do not like them.
You are honking the wrong horn here. Telegram is a type of public forum in the form of messaging app, and it does not need to be E2EE for purpose of reading and viewing resources on topics.
Telegram or Discord are not supposed to be a WhatsApp or Signal. Different tools.