Their operational skills are poor. E.g.: there's a bug in Pokemon Go right now which causes name resets, and there's no way to revert to your old name. E.g.: the new Ingress client is more than a year overdue, and they are facing several hard deadlines related to App/Play Store update requirements.

They have, on the other hand, figured out how to run a live game with Pokemon Go, which is encouraging.

However, I don't think they have the necessary skills to operate as a platform for other game/app makers.