Like for some kids, having to leave a fun play date at their friends house because they have school the next day is crushing enough but probably a good lesson in self moderation and preparedness. That's probably a simpler way to teach self-moderation rather than, here is a bag of cocaine, try not to eat all of it please.
"You see billy, there is a company who is out to get you by stealing all your attention and ruining your life by maximizing profits" is probably a bit complicated for a child.
Also I don't think adults are great at overcoming all their weaknesses, for example, I absolutely love chocolate, so much so that if it's in the house I wish ravish it. So what I do is, I don't have chocolate in the house and it's problem solved.
For some kids not having you tube in their face is probably similar to not having chocolate in the house?
There is a joke: how do you stop a 30 year old man from beating his wife? You hug him when he is 7. How do you stop a 7 year old from being a brat throwing tantrums for chocolate and YouTube? You control your chocolate/YouTube/etc. intake when they are 1 days old.
If parents solved all their problems with the kid by shoving the phone in their hands ["so that brat would finally shut the fuck up"] then of course.
The generation raising children now may not fully understand how critical technology will be in your child's everyday life. You can't just avoid tech, it's literally how every job gets done now, how every leisurely activity is organized or even operated. It's everywhere, unlike chocolate, which can more or less be entirely described as a needless luxury.
This isn't "chocolate" it's "literacy", and by limiting your child's access to it, you're limiting their ability to grow fluent in this new language.
Yes, there are drawbacks and problems, but those will be valuable lessons to learn.
The question then becomes how do you develop self moderation, which has been a question for at least the last 2,400 years with the socratic "how to achieve a good life" (by having an inner life) and the various "religions of the book" which are a proxy to this question, sprinkling in with a forklift supernatural beliefs (the good life is the one devoted to the God superclass, which has private, unknown methods to solve the confusion of reinforcement).
Coming to think of it, it is probably important if the child does not see you as a God superclass: they will try to rely on themselves (although it is a hard game to balance, not to be too traumatic), and they will be less inclined to rebel against you, achieving both their own personhood, but also being set up to follow your example.