What's really absurd about their position is they're taking an anti-materialist stance on the family and its origins. There's nothing natural about the nuclear family, it is a modern construct that emerged alongside the state and capitalism.

My guess is that the way that liberalism and capitalist modernity now pretends to embrace gender and sexuality minorities has caused them to take a reflexive stance against it, as if communism is just reactionary anti-liberalism. Do they even read theory?