Earlier quoted context omitted.
Is Deep Mind a “booming business”? They are achieving great things academically, but their business successes are either kept secret or mostly absent. All I know about is the Google data centre cooling scheduling, probably a big saving for Google but hardly an achievement that in its own professes their business success.
Deep Mind is cutting edge ML in general, right? Doesn't Google actively apply the lessons learned all over the place? YouTube content recommendation stands out to me in particular. Translation and automated closed captioning are also obviously ML based. I'd guess that most of the really interesting stuff would be behind the scenes and not immediately visible to end users though.
Deep Mind is best understood as the following bet: if we can train an AI that can learn from "its environment" and do the sort of things a human would do in that situation, then we have achieved AGI and from that ... business ... will follow. Hence their focus on video games as a training environment.
This sounds intuitive but is actually a very agent-centric viewpoint and most AI doesn't resemble this type of thing at all. Most AI deployed so far doesn't have anything resembling an environment, doesn't have any kind of nexus of agency and doesn't need to actively make decisions that then feed back to its own learning, only make probabilistic predictions. And in fact you often don't want an ML model to train on the outcomes of its own decisions.