I think that's pretty much the problem, rather than VAR - it's the expectations.That's my main feeling about it all. As far as I am concerned, all the Brighton outcomes make complete sense in the rules of VAR, it's just that VAR is nonsense. People want, and thought they were going to get, overturning of poor on-field decisions even if the ref had sort of vaguely seen it. We have created a system where refs are making dodgy decisions based on the hope VAR will overturn it if they're wrong, and VAR not intervening as they don't want to impact the on-field decision. Absolute shite.
There would almost certainly have been a lot more incorrect penalty/goal decisions before VAR, but when a lot of decisions are 60/40 or even 50/50, there are always going to be arguments.
The problem is that fans thought VAR would award their team every close decision, and the "correct" ones are usually the ones that go in the favour of their own team. So, VAR still leaves a lot of fans unhappy. PGMOL responds to the pressure, and starts leaving it more to the ref, but of course the refs are going to make mistakes, or have VAR in their head and so don't give those close decisions, and the pressure comes in the opposite direction of "why didn't VAR intervene". So PGMOL start overturning decisions, and we get accusations that matches are being re-refereed, and VAR makes a mistake, and we get the pressure to go the other way again.
Ultimately our expectations of a system, where humans are still making subjective decisions, is way too high.