segamw I think that if u sign up to play anything competitive ull be expected to try ur best to win by your peers, especially if ure on a team, which the whole purpose of being in one is to compete.
i feel like theres a big difference between being expected to try your best and being expected to be rlly good though, like if you're competing for significant tournament money it might be fair to hold being bad at the game against ur teammate but in tf2 theres less reason to have that high of standards