Most anarchists are not online, or at least not active online. There's an inherent defiance in anarchist circles against imperial / extractive technologies like computers, which is less common in leninist circles where cybernetics has been assimilated (eg. under Allende, or in science fiction like Asimov). To be fair, i have met quite a few leninists who were profoundly techno-critical and did not wander on online forums.

So there's already this biased sample explaining things a little. But "non existing anarchist forces" in the 3rd world is a stretch due to your information bubbles. Can't say they're exactly thriving and on the verge of destroying the State, but there's strong anarchist communities in Sudan, Chile, Syria, Chiapas, Indonesia…