I'm going to try out the new Digital Wellbeing stuff in Android Pie, which lets me set restrictions on app use. But it feels like a smaller phone is a much better solution, as it doesn't have any compromise in terms of portability - what's the point of having a big screen if I'm just going to disable the things that it's good at?
It would be nice if Apple or Google or anyone else could commit to serving the small phone market.