Earlier quoted context omitted.
Happened in my wife’s company of around 40k people. Mail to all, replies to stop replying, many hours to stop the firestorm. Then next timezone 8 hours out started replying. I don’t know why they didn’t just kill permissions to the mailing list.
Outlook has this amazing feature to ignore email threads: https://support.microsoft.com/en-us/office/ignore-all-email-...
https://techcommunity.microsoft.com/t5/exchange-team-blog/re...