How do you know that?
because he doesn't train for the others, dingus. he's not the strongest in any of the main lifts, let alone in any of the goofy lifts they make strongman competitors do. just because he can heave-row 495 for a few and deadlift 805 with straps doesn't mean he'd be able to do the barrel throw or fingal fingers. Even the best powerlifters get their asses handed to them in strongman until they've been doing it for a while.
honestly i'd think his heavy reliance on straps would ruin him as well. he never does rows, shrugs, pulldowns, or deadlifts without straps, so his grip is probably shite.
ronnie coleman, weighing over 300 pounds ripped, has not one lift that would pass in a powerlifting competition. giving him the benefit of the doubt he might have a deadlift in the low 700s and a squat around the same, with maybe a 500 bench raw. Now a 1900 total isn't anything terrible, but consider brian siders.
siders is a guy who has a squat in the 800s, a 650 bench, and a dead also around the 800 mark, logging a total over 2300 in the NERB raw competition. his strongman performances have been good, but he's not going to fight mariusz any time soon. granted that's in a different strongman fed, and maybe ronnie would do all right in the other, but i doubt that as well since he just doesn't do those lifts.