I did something similar. I like to keep my phone limited (the only real useful/joyful things on it for me are family pictures, music and maps). So I used an iphone SE until it fell apart, now I use an iphone mini that doesn't have enough storage so it offloads all but the top ten apps I use.

I didn't make it slow and buggy on purpose though. Apple did that for me with Liquid glass. Which I guess works!