[2022] Rocket League Status on Twitter: "We are aware that Rocket League on PC is not properly closing when players exit the game. We are investigating this issue. In the meantime, players can fully close Rocket League on PC through the Task Manager."

This was fixed a few hours ago btw!

Big surprise, an update broke something.....

Update did not cause this, just coincidental timing. :D (Which is why we were able to fix it without another game update.)