In defense of parents here (and as the parent of a teenager):
1. Many schools require kids to have iPads or similar devices. Those of you saying "kids don't need devices" (especially posting on a site like this) make me laugh if you're insinuating that us mature adult Apple geeks can use technology but the kids don't really need it.
2. It's 2019. I actually want my kid to grow up with a device that they learn the technology as well as responsibility on.
3. I'm a good parent, but I also have a job and a life separate from my kids, and I cannot be watching every minute of their iPad time. (In an older generation, maybe kids would be addicted to TV or gaming consoles that were more publicly viewable, but with iPads, they are increasingly "private" and self-owned devices, used with the iPad's back to the rest of the room.)
4. I want to give and teach my kids both freedom and responsibility. I'm OK with giving the kid an hour of game time a day, to unwind with their friends, and so long as they're not doing anything illegal, obscene, hurtful (etc.) I don't feel the need to police it. Again, I'm a good parent and have taught my kids values. That said, I'm not OK with 9 hours of Fortnite.
The *idea* of Screen Time is a great one and has already been a good help in my family to give the kids some freedom and discretion and exploration/freedom but not let it get out of hand.
The practical details of Screen Time are a disappointment. Apple threw it together and didn't bother thinking through many of its details. I'm very frustrated that it basically barely works, and has enough loopholes/oddities that I think badly of Apple on a near-daily basis that I have to put up with this half-baked solution. And I also resent that Apple designs it so that basically only Apple can manage this. It is difficult for a third-party to come in and have enough access to be able to do it better.
My grade for Screen Time: C+. Apple isn't a C+ kind of company, and I sincerely hope they either fix it or allow other people to fix it, ASAP.