Great read. I have a tiny, inconsequential, possibly wrong correction. You had assumed that the “Negative” word on the internal search engine screenshot was sentiment analysis. I think it was instead a button to report the post in the internal system as a “negative” result as in, not actually matching the search they were trying to do. Sentiment analysis doesn’t seem like it would be very useful in this scenario.
I disagree. The icon of "Negative" is of a red human head. Who would choose that icon for "False positive"? IMO it makes more sense as "Negative sentiment"