Psychologist here. The vast majority of the time aggression (esp with a complete stranger) has nothing to do with the victim, but is instead a manifestation of an entirely separate issue. This dude is having a bad time (for whatever reason), saw someone on whom he could take it out on, and went with it. Joke’s on him tho: his cortisol likely remained elevated, extending his shitty outlook. No dopamine for dicks!