We have seen a lot of favorite teams losing to weaker teams this season, Watford might be one of the few teams stuck at the bottom of the table currently but I think the players of Watford are fighting very hard to try and get their team out from the relegation zone, maybe Watford might still be able to get some points when they play against Manchester United today.
I don't think the result is draw or even Man United lost, United play at Old Trafford and the result won from Chelsea increase their motivation to win again because if they wins, they can go to position 5 with an opportunity to go to UCL next seasons.
I know VAR made a mistake and my team was to profit but I think everyone should realize that no system is ever going to be perfect,,, and nobody wants to make a wrong decision on purpose. I remember Son's red card that was successfully appealed. But yes, nobody should ever play with studs down on somebody else's leg. I saw it in real life and it is not something anyone ever wants to experience.
There are always controversy with all system, teams that benefit from the VAR decision will be happy, contrary the team that loses.