Is it sexist to criticize feminism?

[TAW]

I criticize it on a number of levels and aspects, yes. Feminists are a lot like communists, and if you look at the history of both communism and feminism, you'll see how much they both entwine.
They are both internationalist ideologies, one takes the working class as the basis of identity, the other takes the female sex as the basis of identity.
And just like communists declare non-communsts as fascists and reactionaries, so do feminists declare non-feminists as sexists and male-chauvinists.

Much like how nationalists could label everyone who disagrees as "communists" or how Christians could label everyone who disagrees as "satanists". I think you're problem here is with reactionary individuals who grossly mis-interpret any opposition as purely antagonistic. You're simply attributing this trait to people that you don't agree with, as though no one else perpetrates this kind of behavior when heatedly defending their ideology. This trait is not mutually exclusive to people of ideologies that you don't agree with.

They are both internationalist ideologies, one takes the working class as the basis of identity, the other takes the female sex as the basis of identity.

So you're bashing these ideologies on the grounds that they have followers and a common group of people? That's literally every ideology, ever. Internationalist ideology or not, what you're saying is insane and isn't a direct comparison of communism and feminism at all. You could easily make correlations between capitalists and communist or feminists and masculinists by that flawed logic.