Khan put his people into seventy-two advanced photon torpedoes. But… in order to do that Khan had to have access to his people. The very people supposedly being held by Starfleet to make sure Khan fell in line. Why didn’t he just free them? Why did nobody say, “Hey, that guy is putting those frozen people in the live ordinance he’s designing for us?” In order for any of this to make sense, Khan had to have been the only person building these torpedoes (did he design them AND build them himself?) and then instead of waking his people up, stuff them into the missiles apparently with the plan to piss off Starfleet and get someone to shoot them at him.
Thanos is literally threatening the entire fate of the universe, but captain marvel has for some reason got better stuff do elsewhere in the universe? Also, Thanos mentions that his plan didn’t work because people mourned, and this was because he randomly killed people. Why would he not just systematically kill off sections of the universe that knew nothing about one another, so the population would have halved, and the survivors would be none the wiser – seems much more efficient, and he could track what he had done much more easily.