Here’s an idea for a “distractions free” phone:

Any android phone.

In a work peofile use a primary launcher app that only shows 3 or 4 important apps. Disable everything else.

Lock all the rest in the normal profile with a password that is a randomized 32 or longer character string that you can’t possibly memorize.

Write it down in glaze on a plate, which you smash and store in a bag with some super glue.