Dumb phones address the "kids contacting their parents" angle just fine, you don't need a smartphone for that. I also think that if parents are truly panicked by the inability to contact their child on a moment's notice, that is genuinely an issue they need to work on. It is neither normal nor healthy to feel that way. But regardless of whether they are justified in that stance, that too is addressed just fine by dumb phones.
> Dumb phones address the "kids contacting their parents" angle just fine
There are also other suitable devices. My child has a Garmin watch which can send/receive text and voice messages, but only within a set of pre-configured people. And it can't run or access any ad-ware spam. It's very useful without any of the downsides.
I don't have kids (my wife can't have them, unfortunately). But I absolutely will give my kids a dumb phone if we ever adopt. I wouldn't even want them to have a phone at all, but my wife persuaded me that it's needed in an age where kids can't just use a pay phone to call home the way we did as kids. I am categorically against kids having smartphones.