The long-term solution to the never ending distractions is going to be more tech, not less. We are seeing the start of it with Apple building out the focus modes on iOS, but there's lots of ground to cover. Imagine that all the productivity apps, i.e. slack and email, leverage AI to help prioritize and schedule what you need to respond to. For example, you could imagine your inbox giving you one notification after two hours with a prioritized list of emails to respond to. At the end of the week, if you haven't responded or read emails that fit a certain pattern, it will suggest filtering these emails to another folder.
This is a little more complex with social media, where the goal is to drive engagement time as much as possible. Not really sure what would fix this, other than users manually setting up their own screen time limits. Legislation might be able to accomplish something, but that feels very heavy handed and would likely have poor execution considering how out of touch politicians are. Perhaps Apple could build in some OS features that would identify social media addiction and gently nudge users to take breaks.
The dumb phone idea is interesting and highlights how much of a current issue this is, but doesn't feel like a realistic solution for the broader public