We think we are now 'very moral' but I'm doubtful of that. If you want to play the devil's advocate it's not hard to point out obvious hypocrisies in much of our current social line of thinking. During any era of 'change in one direction' all arguments in the opposite direction or all arguments that have nuance and don't 100% back the current populist trend are utterly oppressed as 'vile'.

Alcohol is an interesting one that goes through phases: prohibition was hand and hand with women's suffrage because 66% of men were wasted every day or every few days and either not coming home, or beating their wives. Without that social context, we look at alcohol differently.

So there's comment here about 'how technology changes people' which is exactly right.

The big one is not how 'horse and buggy' affects dating, it's how contraception has affected us.

50 years ago - sex almost instantly led to children - period - no debate. If your daughter was sexually active, she would be pregnant almost immediately. Your son would technically be a father. This has vast, vast social consequences that affect every part of life. We now have a lot of 'sex positive' people who're ideology wouldn't really even be fathomable just a generation ago, let alone popular. Contraception is as big as the combustion engine.

This article has a lot of interesting detail, going back to antiquity. It really started to pick up steam in the mid 19th century.

https://en.m.wikipedia.org/wiki/History_of_birth_control

One interesting detail is that the sudden drop in birth rates that happened around the introduction of the pill also happened in countries where that never became a very popular method of contraception, Japan being an example.

Around this time, due to commonly available forms of contraception: the nature of sex changed, family roles changed, the workplace changed, gender roles changed, birth rates plummeted, demographics changed fundamentally, family structures changed fundamentally.