But my friend went and played quickplay, he was trying to jump off the map as many times as possible. At the beginning he killed 1 opponent to see his efficiency after the match. I think he managed to jump 48 times in control before the time ran out. He wasn't booted even though he didn't shoot a single shot after the first kill.

Since he kept dying by jumping off the map, it registered him dying. My issue was during Iron Banner, I was holding down a zone and running around the zome holding it down and no enemy came to try to take it and after a minute or so, I was booted for inactivity with no warning. Overwatch does the same thing, which I still consider unfair, but at least it warns you when it sees you as inactive on the game before booting you.