Personally this season has just reinforced to me that football has abnormally large grey areas in assessing whether something constitutes a foul, meaning that VAR is just fundamentally doomed.
E.g. Taking the 3 penalty decisions from last night - personally I think the Sanchez and Alli ones were penalties, and that the Son one probably wasn’t. But I’ve no doubt that lots of people would disagree with me, meaning that whatever decision VAR came to loads of people would disagree with it and say it was a brick show.
Football is a quasi-contact sport, and I think it’s impossible to a) clearly stipulate precisely how much contact is legal, and at which point it becomes illegal, and b) see precisely how much contact there was in any given incident and measure it accurately against that scale. And it’s made even more impossible now that players react in an exaggerated way to virtually every bit of contact, like Son last night. You can’t actually tell how much he was or wasn’t impeded because he throws himself to the ground.
(I also think VAR is being implemented badly, but even if it was being implemented well I think it would be doomed).