Yeah, I see what you're saying. If the stuff that's on TV now were to be played 50 years ago, there'd be people screaming bloody murder and production crews in the slammer
But I wouldn't say morals and guidelines are completely man-manipulated. Humans have always had this notion of how they "ought" to be acting, something they measured against how they were acting and even how they were told by society they should be acting.
There are clues that tell us that something isn't right here- hatred, harm, destruction, etc. have just about always been regarded as wrong. So if something happening leads to these things, then it follows that that something must be wrong. Or so people think.
Take slavery for instance. It has been abolished and people are becoming more tolerant of each other nowadays. So you could say humanity is "better" (closer to the right way) in that way.
If there was no measure of right and wrong, though, what reason would there been to abolish it? Slavery made the South economically prosperous and self-sufficient. The system kept millions of people fed. If the point of life is to survive and thrive, then the South was doing great. Unless it was deemed
more important to uphold a moral standard, or to wipe out a system that created things that were deemed "wrong" (hate, harm, destruction), it wouldn't have happened.
Now you could say, "OK, say it didn't happen. Everyone would have just accepted it and life goes on." But just because abolishment of slavery wouldn't have happened doesn't mean it
shouldn't have happened.
I'm just saying that humans can move in whatever direction they want, and manipulate the laws that govern them all they want, but that doesn't eliminate the possiblity that they ALL could be in the wrong, or right.
The way I look at it, if Hitler would have taken over the world, and brainwashed everyone into thinking that hating & killings the Jews (among others) was OK, then EVERYONE would have been wrong.
I wish I could say something that wasn't just an opinion. I'm not sure if you can prove a higher governing standard exists for everyone. But I know that without humans having a regard for it, however demented it gets at times, there would be chaos everywhere.