"At the same time, consider the words we now consider truly taboo, that we enshroud with a near-religious air of sinfulness. They are, overwhelmingly, epithets aimed at groups.
Gone are the days when our main lexical taboos concerned religion — with “egad” as a way to evade saying “Ye Gods!” — or sex and the body, as when Americans started saying white and dark meat to avoid mentioning breasts and limbs.
Instead, today the abusive use of the N-word, the word beginning with F that refers to homosexual men and a four-letter word for a body part that can be used to refer to women are considered beyond the pale even in casual discourse, to an extent that would baffle a time traveler from as recently as 50 years ago."
Common courtesy has historically been a system of ritual deference to one's social 'superiors'; such as one's father and/or God. What we're seeing in both the USA and the wider world is the rise of more egalitarian, more liberal if you will, ideals of courtesy. For younger generations showing contempt for a random person or group of people has become more risible than irreverence towards one's 'Lords'. The change in our language and what words are or are not seen as taboo reflects that.
This; of course, is exactly the problem for those who love the good old days. Some are offended by the very fact that concepts of polite speech have changed or can change; this denies them the assumed power to enforce the True Eternal Rules over the rising generations of young ingrates. And I'd say that much of the gripes against 'political correctness' comes from a sense that rhetorical politeness towards a group of people is necessarily an act of submission towards them, (as courtesy again has historically been) the ancient fear that there's no such thing as anyone wanting equality but only for Those People to flip the tables of dominance.
Finally there's a sort of 'Donner Party conservative' mindset that views harsh and condemnatory language as inherently more honest than mild speech; a tendency to presume that truth is not just occasionally harsh but that a thing must be true because it is harsh. It's an attitude that proclaims itself to be 'realist' but will in fact resort to needful leaps of logic and even magical thinking when its presumptions are put in doubt. The actual appeal of this attitude isn't its realism but in the way it bases wisdom upon strength and toughness, (manliness if you will) instead of the capacity for complex thought.
But I guess it's of no nevmind really. Their way is fading out slowly but surely and in the meantime they're free to imagine that society is falling into the hands of naïve philistines. I wish for nothing but a pleasant day for all old grumps of whatever age and for you as well dear reader.