«This is like the 27637862487 time that links have been broken due to the exact same action.» I can bear hyperboles but this is a bit excessive, and looks like just another attempt to make this flame bigger: I hope the reality is closer to "two or three times in the past couple of years", and that in any case list owners have been warned. In fact, to compensate such hyperboles, I can't help noting that https://wikitech.wikimedia.org/view/Remove_a_message_from_mailing_list_archive, which I already linked, exists since 2005 and that I assume it's not completely out of everyone's radar.
Adding to what has been said elsewhere in this thread, what needs fixing is this section: https://wikitech.wikimedia.org/view/Remove_a_message_from_mailing_list_archive#Considerations_for_requesters. We should have clear rules (you could just make that advice policy maybe?) and someone responsible for the process. It's obviously not fair to expect someone to pick up these tasks in their overtime, if one wants the process to be reliable (ie timely, policy-compliant and technically correct/non-disruptive).
Nemo