But if they keep the 13 mini, there is not a need for an iPhone SE.
There is not a huge diff in your price scenario from SE to Mini. I have the Gen 1 SE and the 13 Mini -- small diff in size, and the form factor between a new SE and a 13 mini I think will be basically the same (squared off bezel / frame / edge vs a curved/rounded bezel). So you can end-of-life one of those, which I think Apple will do.
I wish the iPhone models / configs were reduced. It's a lot of build complexity. But does that complexity add greater profitability over having a simpler Small=Mini=$499 / Medium=$899 / Large=Max=$1199 product ladder? If the product line-up were reduced to Small / Med / Large, Apple would reduce manufacturing costs, R&D costs, WIP / JIT parts costs, store inventory costs, etc. Or maybe the customers want 8 or more phone choices.
I just want to always have the option to buy a Mini.