Persona 5 already has about half a dozen spinoffs. Enough already. You want to keep fans connected between main series entries?
Don't make them 10 years apart with a bunch of fluff spinoffs that are nothing at all like the main game inbetween. I have zero interest in a *****y mobile spinoff while I wait. It just makes me frustrated that these sorts of things are taking up valuable resources and delaying the main course.