This debate has been going on for years. I detect trolls and sock puppets all the time. But I've never seen any evidence that foreign trolls or bots are an issue. Despite that, one or more posters is completely convinced that every third post or so is from a Russian troll or Chinese bot or whatever. Frankly, I'm at the end of my patience with that poster and if others would report the posts, I would remove them.
Just like "troll-calling", the constant "bot-calling" is more of a problem than actual trolls and bots.