Remake timers and Unfair LP lose

I was wondering why the remake only works for the first 3 mins? Because people still leave the game later on and it can be a 4v5 or a 3v5 and you automatically lose most of the time and its not really fair. For example I was spectating my friend SlayedOut and he was playing Rek'Sai and the Yorik and the Vayne on his team quit after the remake mark. I don't find it fair that he should automatically lose LP for them disconnecting so late in the game. Could you possibly have a remake timer so that it goes off as soon as someone disconnects? I find it super unfair that this can happen, so could you guys at Riot please do something about this?

Thank you, Summoner Born In Blood