It's not a fair game if a player goes afk during the game. There is a huge difference between 4vs5 and 5vs5 in terms of the team fight and etc but players are still getting full panelties if they lose the unfair game
You can systematically abuse that to boost accounts. That is why they don't, and why they shouldn't
It would be nice to extend the remake window just a bit but the problem with making a system like what you want(and has been asked for for years) is that like General Elephant, can be abused for boosting.
It can also cause temptation for more toxicity in which players on a team may try and get a teammate having a bad game to leave so they can get off without losing LP.
