For a perfect object lesson in the failure points of adding Performance Based SR to a team hero shooter one only need look at Marvel Rivals. Currently, the incentives (because of their Performance Based SR system) are to only play DPS, to never swap for your team, and to play Tank and Supports as though they were DPS.
You are rewarded for final blows, so final blow farming is the optimal way to play the game. There’s no need to play it as a strategic team game anymore- in fact, playing for your team will cause you to climb slower than playing selfishly. If your team has 3 dps players and the optimal strategy in order to win is for one of those players to swap to support- whoever makes that swap in order to help your team win will earn less SR if your team does win than the players who refuse to swap and will lose much more SR if your team loses.
In summary, Performance Based SR:
- Rewards selfish players.
- Punishes team players.
- Boosts selfish players.
- Skews the ladder rankings.
- Decreases the overall quality of play.
If you want to incentivize strategic, team based play and increase the overall quality of the games, you must not implement Performance Based SR. We’ve already learned this lesson in OW. And they are currently learning it in Marvel Rivals (because they are speed-running all the greatest hits of mistakes that OW made.)