They might label some people incorrectly as russian agents, but the reality is that there is a concerted effort by russia to undermine the US democracy, mostly directed at the Democratic Party, and making some mistakes doesn’t make them delusional.

It’s pretty hard to prosecute propaganda in the US due to the First Amendment, so it’s not accurate to say that just because the Greens can run, they must not be russian agents.

The concern about the Greens is eminently logical: they are never going to win, so the best they can do is take votes from the Democrats, allowing the fascists to win. This is in fact what happened in the election of Polk, leading to the Mexican-American war and the theft of Texas from Mexico, which was then admitted as an additional slave state. Further, the Greens do little to nothing other than run in big national races, so it’s not a leap to think they’re deliberately running a spoiler campaign.

Finally, none of that has anything to do with the silly attempt to label Democrats as “Blue MAGA”, since MAGA is a quasi-religious fascist personality cult, none of which can be credibly attributed to Democrats.