I don't know what you mean by deserving but the way Arsenal handle the match isn't too nice and well package. Look at the way Tottenham played Arsenal as if they don't used to meet in London Derby only to be playing less of a game. They have less game possessions to than Tottenham and they also have less attempt trying to make th goals, this is why I don't think Arsenal deserve that goal but Tottenham since they are the ones that put everything in that game.
Tottenham deserve a point yesterday because they played Arsenal very well and they created a lot of chances but cound't convert the chances into goals due to how solid Arsenal defense are and how good David Raya was yesterda and with number savings he made during the game which helped Arsenal in the match yesterday.
In this Derby, Tottenham looks prepared than Arsenal, it's not like Arsenal weren't prepared but Tottenham had everything on their mind probably because they have won some matched before now while Tottenham is still struggling to balance their game in matches they have next. However, logically one might think that it was because it's away match Arsenal didn't put mouth efferot as they expected.
Arteta was also prepared, he knew is going into the match without tow of his key players Odegard and Declan Rice, and these two players are very important in Arsenal's squad. Notwithstanding, London derby is always tough that is why Arteta wanted to be safe which is why he make sure the defenders do the right thing always.