Bad rounds would "hurt" the average only temporarily, also the ego pain will pass.
Eventually, the bad scores will be replaced by a player's good scores, and these are neccessary to tier up!
I agree: Good sportsmanship to stay till the (bitter) end, honouring the other's good play.
It's self-evident to quite a few here (add me) but not to all. To their defense, let's not forget it's only an online game of virtual character where some may think they have no obligations to their fellow players. Furtheron, stroke play can be continued even if all but one quit.
Nevertheless, it leaves a sour taste.