Limiting themselves to just one major release a year for Awards sake would be a terrible idea and sales would be barely impacted.
God of War sold around 8.5m in 2018
If Spiderman didn't release God of War might have sold marginally better... but we're talking in the 10k-150k range, it's not worth missing out on those 11m sales from Spiderman. Delaying Spiderman to 2019 would have just meant it impacted Day's Gone & Death Stranding instead.
Basically the damage from releasing multiple big games in a single year is negligible and the benefit vastly outweighs it. The only reason to not have released both GoW and Spider-Man in 2018 is if that would have left 2019 with nothing.
Unless they release the same month their impact on each other isn't worth worrying about. It's important to spread releases out, but not releasing in the same year at all is taking it way too far.
Right, taking a game out of the PS4 library doesn't equate to it's sales being dispersed to all other games in the library. Games sell consoles, so many good games benefit each other via consumers who purchase a console for Game A, leading them to buy Games B, C, and D (games they would not have chosen to buy a console for).
I can't help but feel this thread is either a troll, or OP is acting naive. We're just talking common sense.