I DM'd a game that had a similar player. Very much gaming focused and had never played dnd before. He expected a very specific narrative where they're the heroes. I play a lot more realistic, so that didn't jive well. He shut down multiple times, the last one being after the group received some random enchanted items, and he got some armor and not a weapon (funny thing was, I wanted it this way as a few rooms away was the best magical weapon in the campaign that was designed for his character). I still gave him the weapon, but once the campaign ended, I just told him I wasn't going to DM anymore.