The only series that release "every 12-18 months" are sports games and Call of Duty, and I can assure you that the overlap between that audience and the Persona

The only series that release "every 12-18 months" are sports games and Call of Duty, and I can assure you that the overlap between that audience and the Persona one (which has five main-series entries of which barely anyone has played the first two) is extremely small. Have you considered that you may just be very out of touch?