Every call is subjective. What do the eyes of a human being see or not see. You can't prove a ref didn't see an obvious penalty,
Instant replay is the same thing. Purely subjective to what they are seeing. You and I may see something different from what they see. If it seems obvious, the announcers come on with some BS that the control center has different angles and must have seen something the general public didn't see.
It's something that can't be proven! Back in the day when players didn't make much, you could find players to shave points etc. You can do that these days with the outrageous salaries, which is why they implemented instant replay.
Also, remember that the NFL has the same license that WWE has. It's an entertainment license and they have the right to steer a game the way they want.
The hits, injuries, and crybaby players are real. The NFL is basically a slave owning entity that owns their players and use them for entertainment purposes for the masses to enjoy.