If he had ample space to go around you to exit, then fuck him, you're fine. Standing in the doorway while traveling is normal at all hours, but during busier hours, you want to step off the train just off to the side/outside the door so folks can get in and our without the entryway being blocked by your body. But if it was a near-empty car, then that guy probably just wanted to be a dick. Just have general spacial awareness is the main idea