You just figured out your own problem your using wireless to connect to your router. That = lag. Are you on a t.v. or a gaming monitor. An HD t.v. can induce another 70 or 80 milliseconds of lag even if you are in gaming mode. Ad this to Your ping to host which on PS4 can be high due to the limited lobbies available which means you can be in a lobby thousands of miles away.Using up bandwidth and then stopping will not effect anything. Kind of like putting a bandage on a kid. They think it makes it all better so they stop crying. You believe it works so you play better. I have seen so many videos of people claiming lag and then you watch it and slow it down to frame by frame and they are missing their shots or the lag is not as bad as they claim.
Get off your high horse, I am a physicist and do some programming and know what lag comp is.
People with optical fibre in UK should be able to find low ping games, something PC servers have been able to do for the last 10 years especially for games with high player numbers like COD.
you're a physicist yet think having an optical fibre connection would give you a lower ping? , not sure how or the whys you think pc servers have been able to do this for 10 years but anyways..
as for the uk.. the main supplier of fibre in the uk is virgin.. which is also the worst isp to have if you are gamer .. weird how that works isnt it