I still think $350 is a lot, but when you have ADHD devices with a lot of features can be very detrimental to your productivity and your well-being.
My last dumb phone, which I bought to carry while cycling, cost me $30. Sure, it was ugly, but since the point is to not take it out of your pocket and play around with it, who cares?
This phone strikes me as the veganism of dumb phones. You want people to acknowledge the "sacrifice" you're making, so you're going to keep it visible, while you self-consciously don't interact with it.
I could speculate about personal insecurity issues, but instead will simply note that not everyone comes from the same place you do or share your particular concerns or needs. It is a big world, exploring it some might be good for you.