Matchmaking
Along with lag measures need work
Sadly COD allows unstable clients into the game along with the fact most consoles have a stupid high ping.
What am saying the game should be harsher if you lag should not allow you to play simple.
Also with most consoles being wireless means high ping at random times.
All COD games have had this issue
Tbh the game should tell you when your unstable and ask for you to fix it.
Btw test the knife offline when online with mates
Notice the difference that lag well not the true name