Why is it no one has fixed the afk problem in this game?
No you cant abuse it, it is too easily tracked. No assholes typing to leave when you do bad aren't a reason not to, that's an excuse people use to be lazy. There is a chat filter, a mute option, and a mute all option. If you are being abused, it's because you wanna be. There are few games unless you're playing with friends that doesn't have at least two people saying you suck or report such and such for such and such.
If you wanna argue no because assholes, then here's the argument everyone gives when you get punished for getting mad at trolls and assholes: Mute and report after. If no matter what you have to already mute and report after, you may as well not have to waste time on winning multiple matches to catch up to losses because of afks.