I went to school with some Russians so I was often able to pick out troll profiles based on slight grammar mistakes and word choice. I imagine LLMs are going to make this harder.
I'm a Russian and sometimes I think they did evolve to levels that are harder to detect now. Or I am just more paranoid from seeing the trolls and over the place and knowing about LLMs. Or there are more people who got converted by those trolls into zombies. Or all 4.
Their bots are not very difficult to notice if you look at profiles. Weird usernames used to give it away too