I think he'll be able to do some good stuff on the software side (i.e. the industry is full of AI cowboys who can't code) but on the fundamental side it's hard to see him doing much.
In terms of research background, you're right. But he's someone with a history of original thought and as he states, it's not clear that we're at the stage of machine learning where useful contributions from newcomers taking a different direction are vanishingly unlikely.
I'm sure OpenAI wouldn't have offered him a job if they thought he couldn't contribute anything of value.
I think he'll be able to do some good stuff on the software side (i.e. the industry is full of AI cowboys who can't code) but on the fundamental side it's hard to see him doing much.