This is the best frame (from the best angle) of the incident. It is seemingly not the one they used to determine if it hit his arm—they used a worse angle from further away, looking on from behind the goal, which made it impossible to say if it hit his arm.
I have seen all of the angles and I think it just hit his hip as he tried to tuck in his arms as tight as he could and turn away from the shot.
Disallowing that goal is not only stupid from an evidence perspective (read “highly suspect) but it violates the spirit of the game, as what is he meant to do there.
There’s also no consistency, as goals from similar incidents have been allowed and disallowed, seemingly with no reasoning for why the decisions differ. It seems, from an outside perspective, that they just make up the rules to suit what they need at the time.
That certainly seemed to be the case today in this match.
And Atwell is literally looking straight at the incident the entire time!
I personally believe, due to the adoption of VAR, they have intentional made the handball and offside rules ambiguous so that there is a leeway in practice when reviewing incidents, allowing them to chose when and how to attempt to influence match outcomes.
And today was an especially blatant example of them doing it throughout the match to aid Spurs at the expense of Brighton.