Valorant is a gamble you either get the teammate that drops 30 kills or the shitter that goes 0-30. I say every game should be determined on the players KD so its fair matchmaking, exterminate shitters.
Hot take:
There should be no hidden MMR because ranks are already there. For example, if you are a silver player who plays in gold-plat lobbies, you are playing against players of a similar skill level. Essentially, it makes it harder for you to climb. If you truly deserve a rank, you will naturally get there. If your skill level doesn't match the rank, you will naturally de-rank. Its either ranks or MMR, only one.