If he was visibly drunk while boarding, they shouldn’t have let him on, although I know that would not be an easy task.
To be honest, I don’t even know how uncommon it is for a small percentage of passengers to be ‘mildly pickled’ before taking their seats.
Playing size was 6’7”, 315 pounds. Likely heavier now. All-Pro offensive lineman for ten years. Likely had at least one fat contract. He’d be hard to move. Born in Haiti. Might be hard to reason with.
I am of the perhaps unpopular opinion that there should be the requirement to subject to a breathalyzer prior to boarding and that alcohol should not be served in airport pre-boarding lounges or on planes except for perhaps a 1-2 drink maximum.