The problem, as others have said, is the bias (unconscious or otherwise) that is inherently shown by referees towards the "big" clubs, and their big name players. The example of Haaland getting away with dissent (on the pitch at least) for screaming in Hooper's face, yet Bogle gets booked 3 days later being key.
The players and managers at these clubs now have so much power and influence, that referees are terrified of upsetting them. Hooper must have thought he'd got the absolute dream fixture immediately following his man city fuckup. All he has to do is not upset Klopp, or Van Dijk, and he's back in the clear with the authorities. Little old already relegated sheff utd don't actually matter. Even if (as he did) he goes on to make mistakes that cost us, nobody is going to kick up a huge stink about it. Had he (correctly) awarded us a penalty, and then sent off Nunez (2nd yellow) for the scissor tackle from behind on Bogle, Van Dijk would have been looming over him, screaming in his face on the pitch, Klopp would have lambasted him in interviews after the match, and the media would have highlighted his performance (again).
As it is, the expected team won, there was a bit of talk about the decisions, but it's all forgotten now.
I think some referees are bent. I don't think Hooper was bent on Weds night, I think he was scared of causing more controversy so soon, so he erred on the side of caution on the pitch, to our detriment. I genuinely think that with another ref, who hasn't been under the spotlight recently, we get at least one of the 2 "big" decisions the other night. We either get a pen, or their 2nd goal doesn't happen.