I have zero doubt he is VERY accomplished in his chosen discipline. But how are these displays indicative of ANYTHING resembling a true attack? Guys half-running at him with no actual stated assault purpose.
Some dude with good hands, who seriously wants to put on the hurt, will punch 10 holes into Seagal's head before he even has a chance to choose a twisty-arm counter maneuver. Or a very large and powerful man will simply run him over.
But if you're trash-talking ol' Steven at the bar, without a defensive or offensive strategy, or attack inclination, watch out!