I wouldn't be surprised if the opposite was true, at least with the theory part. AI didn't really go anywhere for decades, because people focused too much on theory.
Otherwise, there's a lot of data and hardware at your disposal, even from the comfort of your home.
> Wouldn't it make more sense for him to join a cutting-edge team, like DeepMind or OpenAI?
You mean they guys that are training with videogames that people like John developed?