I suppose when they were dropped in iOS 12 it wasn’t nearly as old. They’ve done well to keep the same devices supported since then. You probably don't want to

I suppose when they were dropped in iOS 12 it wasn’t nearly as old. They’ve done well to keep the same devices supported since then. You probably don't want to buy a new phone again, but I recently went from an SE (2016) to a 12 Mini and can tell you it's a pretty great device. If the new SE feels too large, you might like it too. More expensive, of course.