The fact that repositories even have "codes of conduct" is Orwellian on one hand and a sign of idiocracy on the other.
"We (the maintainers) don't want to work with you if you do/believe X" seems quite sane to me, it's their choice after all. If you don't like it, fork it or move along. Code of conducts are supposed to regulate how contributors to the project interact. Especially nowadays, where projects can come with a significant social aspect/dynamic, this becomes important.
Codes of conduct.