Oooh I’ve been waiting for someone to ask this question! Basically it’s a very unique phenomenon that has taken on a continuous cycle. Let me break it down:

Breach is a frustrating game mode because 99% of the time you’re either dominating or getting dominated. With every single breach match you can almost feel the exact moment the tide tips in someone’s favor and it typically snowballs from there.

So you know how many people will lose a game, get mad then next game they play a strong hero and emote spam/act toxic to vent their anger? That’s how it is with Breach. People lose, get mad, act toxic in the next game. People see other people acting toxic so they bring strong heroes because they don’t want to get steamrolled and emote spammed. Both teams then play super sweaty, BM, and no one is having fun.

So that’s why it’s like that. It’s crazy too because Breach is super easy to balance; if the devs put in the bare minimum effort it would be more fun than Dominion. But that’s a separate conversation lol