Have the Dems fucked up a lot? Yes. But short of an actual Civil War, the only way to curb this madness is to vote Dem in November and flip the legislature. The GOP's fascism was hypercharged by targeting the Republican primaries. We can do the same the other direction on the left, and we've had recent success doing just that. And that terrifies the Nazis more than anything.
So they go to our online communities, pretend to be one of us, and try to convince people that the Dems who have failed to stop the GOP are the real problem. The fascists are very active here and elsewhere trying to convince leftists not to vote for the one party that can actually stop the GOP. They say that the Dems are no different than the GOP and try to get the left to split the vote in a manner that will ensure Trump and company win.