I agree with the last half of your analysis. It could be likened to the increasing tuition and school book fees in college, a result of universities knowing the government will give/loan college students a hunk of money. No longer is poverty an excuse for not being able to afford college.
Heard it all before, brother. All due respect, this is a very, very, very old song to sing.
"When I was young, we were taught to be discreet and respectful of elders, but the present youth are exceedingly disrespectful and impatient of restraint".
~ Hesiod, 8th century BC
The timeless critique of the youth might at first encourage a dull yawn, but I think these delusions require a more complicated explanation than "the aged population is just being a bunch of grumps". Psychologically we all think back to our adolescence and all the silly mistakes we make. We don't want others to go through the same thing and in that sense it is a sort of selfless complaining. At the same time we feel frustrated by the ignorance that comes with inexperience. Adults would much prefer their children to skip their "glitch" ridden teen years. Many adults would take a teen with a wrong opinion over a teen that's still pondering the issue and stuck on the fence.
I could go on to say that adults have these expectations of human development because they're lazy, entitled and want everything handed to them without having to work for it.
But of course that would be generalizing the psychology and reasoning of an entire demographic, which would be very stupid of me to do. The more appropriate answer: It's complicated.