I'm not defending him . . . But it does appear that this thing kicked off as he approached the seat. The video doesn't capture the whole of the incident, that may be coincidental or it may be on purpose, but the video certainly does not cover the whole of the incident & most importantly the trigger event ?
Flying for some is a terrifying experience & the fight or flight hormones kick in which some people cannot handle. Air rage is closely linked to road rage & anger is an emotion that is born from fear.
The gentleman does come across as what I'd politely class as 'special', there isn't enough material to work with, but I'd bet this constitutes almost normal behaviour for him !
I'm not defending him, but I feel this is a non event which is totally irrelevant to the anti-racist cause & the coverage it is enjoying may have it's roots in Ryan Air bashing.