These days the government forces kids to be adults at 18. A few decades ago, a disturbed or emotionally unstable kid could have his parents do things like pay for stuff and handle medical issues.
Now, though, medical issues cannot be discussed with parents once the kid turns 18 (like a psychologist or psychiatrist can no longer chat with parents). Financial issues likewise, the kid must handle that too. Bank accounts become viewable only by the kid.
Conservatorship is about the only way a parent of an AS or Autistic or Down kid can stay in the loop and handle things the kid has difficulty with.
Doesn't matter if a parent is paying for their kid's college, he doesn't have the right to manage the account. A library won't tell a parent what library book the kid has on reserve so they can't pick it up for them on the way home from work. We can thank the libs for all this. It's the libs who have the blood of those little children on their hands.