There are considerably more aspects to hitboxes than just the contours of all a player's hitboxes in aggregate—head box size/shape, limb box size/shape, individual hitbox placement during animations, transform during animations, placement relative to default weapon reset position on other characters, placement relative to recoil patterns on weapons, yadda yadda. And those are just factors that are game-agnostic—there are almost certainly very, very particular considerations contingent on this game's specific damage modeling
I think it's totally possible that e.g. Wraith's hitbox gives her a huge advantage and that Gibraltar's gives him a huge disadvantage. But the information that is currently publicly available is not detailed enough that that would be self-evident—even if that video's findings are correct, there are way more factors at play than just "this is the rough shape of all possible hit zones on a character", to say nothing that there are already clear instances in the game when blood/sparks splatter doesn't correspond to damage done.
I think it's a totally reasonable consideration for players to be thinking about in choosing characters or thinking about how the game can change, but audiences who are not familiar with the specifics of the game's damage modeling or implementation combat systems should temper their criticisms and complaints. If Wraith, Bangalore, and Lifeline get chosen all the time, that says more about players' perceptions of their relative strengths than it does of any actual variance in winrate or of specifically the role that specifically their hitboxes play in that winrate.
