It seems typical that every generation rebels against its elders to some extent, and that most elders don't approve. Right or wrong, most people resist change, especially with age - though most elders don't realize it in my experience (and stridently insist otherwise).
Your last sentence is probably right. While you may not approve of Millenials lifestyles, I suspect the elders from the 70's approved even less of Hippies. And I suspect they felt they no longer "ruled the world" (your description). While we weren't all hippies, our generation was influenced by their movement and others. Just as Millenials seems to be laying waste to conformity from your perspective, hippies started that ball rolling. [Ironically hippies grew into Boomers, an argument can be made that we made things (much) worse as adults than our youthful idealism might have promised - but that's another well worn thread. Maybe Boomers, former Hippies, have little room to criticize?].
All the above can be written about Bohemians, swing kids, flappers, beatniks, hippies, freaks, punks, mods, new romantics, generation X, emo, hipsters, millennials, etc.
As for the breakdown of the workplace environment as you describe. If the purpose of work is to increase productivity and offer more valuable competitive products and services, the rules you describe above may be beside the point. That's not all bad IMO. I don't miss the days when we all wore suits to work. I don't miss the days where everyone smoked at work, and you were "out" if you didn't. I don't miss the days when women and minorities were openly treated as second class citizens. I don't miss the days when promotions were awarded based on seniority over merit, and certain groups were excluded regardless. The decrease in stay-at-home-Moms has necessarily altered the workplace. Technology has/is radically changing the workplace - we can often work together without physically being together - work hours aren't as necessary, neither are dress codes. I could go on and on.
Change is good, though it's two steps forward, one step back in the long term. We may go astray with change in the short term, but so far we seem to get it right long term. I hope that hasn't changed.
Sorry if this isn't what you hoped to hear...just my 2 cents.