> I'm surprised no one ever speculates about foreign meddling in media such as the chans
I feel like plenty of people do speculate about that - and for good reason, given that anonymity includes not knowing the nationality of any given "anon" (and even 4chan's operators won't ever really be able to know, given how common it is for non-Americans to use American VPNs for other things - e.g. bypassing region locks on media services).
Same goes even for places that don't have a concept of an "anon" per se, like reddit or even Hacker News. I might claim to be an American citizen living in the SF Bay Area, but that doesn't mean I actually am an American citizen living in the SF Bay Area. Y Combinator might be able to see that my posts are more-or-less consistently coming from American IP addresses (barring a point in time where one of the GeoIP data providers believed my home IP to be Canadian, thus locking me out of various content on Spotify and shunting me over to the Canadian version of Newegg, much to my combination of chagrin and amusement), but it's quite possible that those IP addresses are just the far ends of VPN connections from, say, Russia.