https://news.ycombinator.com/item?id=45171200
I use this method ^ which lets you keep essential apps but otherwise have dumb phone (no browser, no App Store). Highly recommend.
On the other hand, I have turned my laptop into a dumb computer using cold turkey blocker. I've never seen anyone talking about this here. I'm a standard user (for hardening reasons). And set up so I haven't watched YouTube largely for years because it's blocked and not at all in the past few days. It's flexible to configure and then because it's literally impossible to bypass you never try and then just end up living a calm life. (No ai, no reddit, no crappy news sites, etc.)