It could be that Conte was looking ahead to the final two fixtures, trying to play mind games by rubbing salt in the wound, hoping Arteta would dwell on this game rather than look to the future. Or maybe he was just being a prick after a big rivalry win.
Either way, did Arteta really have that much to complain about? One could argue the penalty was somewhat soft but the push in the back by Cedric clearly prevented Son from putting his head on a potential goal scoring opportunity. I’m not saying he would have scored, but one would expect a player of his quality to at least put the ball on frame.
As for Holding’s two yellows, I don’t see how the referee could have given him any more chances. In 32 minutes of action he committed 4 fouls worthy of a yellow, all of them on the same player. Arteta should’ve been more upset with him rather than the referee because his lack of composure almost singlehandedly cost his team an opportunity to clinch Champion’s League football next season.
Unfortunately, I still expect Arsenal to win their final two matches. Conte will likely have to settle for the Europa League next year if he happens to stick around.