Post-game Mute Function?

So quite often playing games now I'll mute every single member of my team the second someone even looks like they're going to start flaming someone else. I don't want to read that. I don't what to see rude people calling each other names and getting into fights. I don't care if they're doing it to me or someone else or whatever. I'll mute. Not interested in League's dump of a community.

However this doesn't carry over to the post-game scoreboard chat. With my potato of a computer I'm always the last to load in and out any way, and I often get treated to 10-20 lines of abusive shouting about whose fault what was and calling for reports for playing bad and all manner of toxicity and I'd just rather not see any of that? Why doesn't the mute function mute people in the client as well as the game? Could this possibly be a new feature going forward? I was very surprised to see that it wasn't already a thing.