Reminds me of the one hilarious thing about the USSR and when you look into their histories. They were basically exactly as uptight as the US despite lack of any religious motivations, convinced that the west was out to corrupt the youth just as the US was convinced the same about teenagers. They abhorred homosexuality despite a lack of religious basis for it and no real costs - it would save the state money to have their 'confirmed bachelor's living together openly.

Really it is an authoritarianism thing over any other professed values. As generations of teenagers have told anyone who will listen what they really can't tolerate is anyone openly deviating from the norms - not as a result of any actual harm but because they fear and hate anyone who questions them. A non-authoritaran system doesn't give a fuck about trivial things and has a live and let live attitude.