I've heard it called engineer's syndrome. "You start believing that since you're an excellent engineer in one specialty, then you're a friggin' genius in everything you do, because it's all the same, really" [0]
It apparently affects physicists too, and must be common enough to warrant two xkcds. [1][2]
It makes them great for advice because they arent going to use emotions or hopes.
But also, in this case, me and my wife are 2 business owners that have been doing it for a decade. This person started a few weeks ago.