Make a list of people who do it. Which is not hard, lots of people already shamelessly admitted to doing it in aoezone.
Create an organization of like-minded guys and gals (could be called the ALT+F4 HUNTERS)
Everyone in this organization helps in updating the list of easy trigger alt+f4 scum.
If you manage to grow the ALT+f4 HUNTERS big enough you could potentially pay the alt+f4 scum with their own medicine, by instantly doing alt+f4 every time you face them.
Best of all is they can't complain about uncivil behaviour, after all you're just doing to them what they already do to others.
I wonder if there is stats on how many people leave the queue when they see the map. And I wonder if it even increased after the prefered map non-sense framing people that they have the natural right to play on their prefered map EVERYTIME and that others dont deserve to play on their map with full seriousness. Matchmaking is a compromise and we just could end up destroying matchmaking from its core just because people do this ****. Its so weird they dont care about elo when it comes to leaving the queue and get the auto-loss but they still care about that much that they dont leave for a lobby.