So I think a claim that "controlling parents" -> "adrift young adults" would be hard to support.
Kids need to learn from mistakes, but if not monitored, you can hit the opposite end where the lesson isn't learned because there are no real consequences. For instance, goofing off in high school won't give you consequences until you graduate high school at the earliest, and possibly not until you graduate collect (still goofing off) and suddenly hit a wall in terms of what you can get employment-wise.
And yes, sometimes kids get away with things if they aren't monitored 24/7. They're supposed to. Figuring out the boundaries of attempting that, and dealing with the consequences when you fail, is a very important lesson for children.
And frankly, the kids have the upper hand. Monitor texts and they'll switch to "Finsta"—or whatever came after that.
All it's going to do is mess up their ability to understand trust or cause them to avoid taking any sort of basic social risks.
Those are learning experiences too.
So why should I, or do I have a right to, keep my kids from doing the same?
We aren't only the product of our positive lessons. A lot of life is learned through burning yourself on the hot stove. And by and large, it usually doesn't kill you.
IMHO, no humans are self-actualized enough to possess omniscience and act ethically. We have too many neuroses.
And, at the more obvious end of the spectrum, all of the suburban crowd complaining about how their children fail to launch, lack initiative in life, and aren't independent.
After their entire childhood was spent being monitored and constantly corrected by the parent.
The mind boggles.