I think their approach to team killing is part of why the user base is so forgiving of team killing.
It is included in the training and baked into the game play by having generous respawn limits. There are jokes about it baked into the promotional materials. Everyone expects to be team killed on accident, so people tend to assume any team killing is accidental. People who might otherwise team kill on purpose will either get their fill through accidents or will not get immediate reactions that feed their trolling.
So by keeping the team killing in the game they have also defused a lot of possible trolling while also having people just accept it as part of the game, especially when non-player initiated features like turrets and backpacks are the worst offenders for team killing.
Finding it funny is a great approach, kudos to the devs.