Are liberals more of a threat to communism than the right wingers?

liberal are still capitalist

both are bad, but both sides can be converted.

I feel like this is why Stalin was a good thing. Russia could've turned into an anarkiddie sjw hellhole if someone like Trotsky was in power. Stalin showed how communism could be actually reactionary and I think it attracts a lot of edgy right wingers.

dude what

Liberals are right-wingers. Expect them to join the bourgeoisie when the shit finally hits the fan.

still not convinced it isn't a troll, those posts are unfathomably stupid
then again one should never underestimate Americans in that regard, that's what I've learned

Considering that Liberalism has done more to destroy/hinder communist movements worldwide than influences from the far-right have, yes.

When and why did modern SJW idpol form? Is there any writing on this, from a non-rightist perspective?

Yes.

Post modernist, third wave feminist, years of fermented hatred, morale relativism.