I thought I was going crazy searching for this discussion until I found I wasn't the only one who remembered it existing.
Here's an archive.org link, and a screenshot of how the page currently appears to me:
Why did the Community♦ bot delete it?
It's a valuable discussion on an active proposal.
After it disappeared, users started asking the same questions all over again..
After reading Shadow Wizard's answer, I have more questions about the system and whether it should be more forgiving. I've posted a followup bug report here.