The PSP had exactly zero games that ever interested me in any capacity over the course of its entire life, while the DS had a few. Even Vita had one game that interested me. My cousin bought a PSP because that was the ‘cool’ thing to do, but then he had the same problem with it that I had, so he just proceeded to keep borrowing my DS instead.
So, DS, PSP might as well not have existed as far as I’m concerned.