It's because "Three's Company" aired in 1978 that trash like "Friends" airs today.
We can't leave the bar alone. We either raise it or lower it.
I'll let you guess which is more likely.
Just because you call something "prudish" doesn't make it wrong. We call that "ad-homenim attack" and it is the sign of a weak argument.
The "prudish" sexual mores of women remining chaste until marriage (including modesty) and remaining faithful within marriage are the bedrock of any society. That makes them "good" as well as "prudish" and morals we can only wish would return.
Shalom.