I want to be clear that I’m commenting solely on the expectation of a swifter response from leadership in the original email thread and not on Marcan’s decision to step down, which I can’t be the judge of.

One was a direct result of the other. You can’t separate them.

they might try to resolve things in private first (seems to be the case)

Neither of them have the authority to resolve it in private and it was clear by the third message that there would be no resolution between them.

they might want to chime in when people have calmed down

They didn’t calm down, it was plain to see that things were only becoming more and more heated until the conversation reached a breaking point.

Marcan asked Linus to come in and make an authoritative statement and end the bickering and he did not. Hector interpreted that as Linus being apathetic (which is a rational position given the time that had passed). I’m not going to try and judge Linus, I don’t know what was going on in his life at the time, but it was, as Hector stated, a failure of leadership regardless.