I think the issue with the refs is how complicated the nfl has made the rules. I dont know how you tell what's pass interference and roughing anymore.
Rule changes and stupid rules, how they are told to ref, all factor in. Also it is not a easy job, most of us would want to watch the game or the ball.
But I agree some bad calls, and bad no calls.
The nfl owners dont put a lot of money into ref, and they dont want to pay them much.
They should hire young guys and train and pay them for 3 years before they start to do games.