Russia has been infiltrating American dissident groups for decades. Just as every country infiltrates dissident groups in its adversaries. Way back in the day, it used to be mainly left-wing and anti-war groups. But in recent decades, they've increasingly targeted libertarians, Tea Party, militias, white-power/racists, and whatever.
This is true to some extent --but people sympathetic to some of those causes will not like to hear that.
Plus, we've been there and done that too --but then it's "whataboutism".
On the other hand, we need to get a handle on this and temper it --not that we or anyone can completely remove this kind of influence-- t's just a part of information warfare. But now we have Democrats on the one side oblivious to their contributing to the Russian effort (in sowing discord) and the right playing it down. It's a partisan mess.