This is precisely the first time I've ever heard of political correctness being rooted in anything other than cultural marxism.
Hardly a surprise. People like you will never understand that people like me grew up in your world. We remember being looked down on and ostracized for not being religious, or religious enough. We remember that having a tattoo, or a piercing, or hair too long meant exclusion from "polite" society. We remember when women were best seen and not heard. We remember the rigid "manly" codes that literally killed countless boys before they even reached adulthood. We remember the "conventional wisdom" that tore apart entire countries for not being sufficiently advanced or obeisant.
We remember all the racism and sexism that served no purpose but to preserve power. We remember "good ol' boys" and unspoken rules that made life bewildering to those not in the know. We remember having to respect our elders, our supervisors, our officials, no matter what they did. We remember being told to keep quiet for no reason other than widespread knowledge of the crime was a worse sin than the crime itself.
And yet you have the gall to throw "cultural marxism" in my face as if we in the west didn't already have a culture of stifling anything that dared move in a direction the herd didn't approve of. You and your ilk bleating and moaning and complaining, confused at the world they live in, too stupid or too proud to understand this very thing you've ceaselessly complained about for years is the direct result of you wanting exactly that, just to your own specifications. I hope you choke on it.