Post Game Lobby Load Times

League basically bricks my computer for 2-3 minutes after the game. I can't do anything except wait for the post game lobby to appear. I have the 'close client during game' option unchecked. I've done a clean install twice, no changes.

Computer specs: Ryzen 3800x 1TB Samsung NVMe 32GB of RAM 1070 ti

It's not my computer, because he's a monster. In no world should he rip through 6K exports faster than it takes the lobby to finally post after a game is over. HALP.