I'm still quite a keen Ingress player, now all the well known Ingress hotspots (we call them farms, don't judge me) are full of kids standing around.
I doubt Pokemon has as many benefits for travelling as Ingress does, one pokemon stop is pretty much like another. Whereas in Ingress it's a matter of necessity to visit other distant 'portals' to link them up, very satisfying by bike over long distances, as the longer you have to travel, the more likely that another player ruins your chances of completing your field while you're riding there.
Pokemon seems lacking in depth, I've been surprised to see so many adults playing it.