https://www.dota2.com/newsentry/3692442542242977036
Today, we permanently banned 90,000 smurf accounts that have been active over the last few months. Smurf accounts are alternate accounts used by players to avoid playing at the correct MMR, to abandon games, to cheat, to grief, or to otherwise be toxic without consequence. Additionally, we have traced every single one of these smurf accounts back to its main account.
Hit the nail on the head, I'd say. Some future competitive game that endeavors to weigh in an evaluation of personal contribution over just the binary win/loss condition and that implements ways to automatically mitigate the negatives enumerated for long duration matches is going to start off in a really good place.
Handling those issues honestly seems like Step 1 in tackling the kind of negativity that is notorious for cropping up in these sorts of games. If everyone's having a better time and doesn't feel punished for things outside of their control, it seems reasonable to assume that the baseline behavior will be a lot more chill.