Hassabis is absolutely a nerd. Joint honours physics and maths from Oxbridge and a PhD in neuroscience (and a Nobel prize in none of these fields).
His driving interest was always games (master standard in chess at 13, five-time winner of the all-round world board games championship, video game programmer in his teens then his own studio in his 20s).
He's the end game boss of nerdland.
Yeah but the dictionary has "intellectually passionate but socially awkward, or someone considered unstylish and lacking social skills". I think he might be a bit social.