[....]I also don't know for sure whether the VAR decision for the goal scored by Garnacho was correct or not because after that incident it was Arsenal who managed to turn things around.
What are you trying to say here? Arsenal's last two goals has nothing to do with the disallowed MU goal. If you have a problem with the call then point it out on a technical level and not come of as someone saying MU was robbed of that goal so Arsenal could win. Garnacho was offside by the slightest of margins.
If in the Manchester United vs Arsenal match there are still those who blame the referee's decision, it is a sign that the Manchester United fans are trying to dismiss and do not want to accept the fact that they lost to Arsenal. Even though many of Anthony Taylor's decisions are often controversial, in that fight, in my opinion, he showed fairness and professionalism.
I agree, for even if you re-watch the match it is clear that Arsenal were superior to Manchester United at many points, so the fans' outrage is nothing more than frustration at the defeat. After all, even assuming that their goal would have counted, it wouldn't change anything, for the score is 3-1