I mean sure, that is how some (mostly strategy) games do it, but for an FPS, figuring out where the buffer should be would be a programmers nightmare. I guess you would have to try to calculate all possible line of sights a player could have within some buffer time and then all players that could in theory enter them… Add physics and it is practically impossible.

Also, corner hack is useful enough and it does not address aimbot. IMO the answer is some combination of human moderation and ability to play with “friends” instead of randos. E.g. you could ask people to like or dislike a player at the end of a match and try to pair players that liked each other in the past.