In the current or proposed approach, who benefits?
Having a user data derived wall of shame benefits the userbase by increasing search quality, which directly benefits Kagi in the form of a better product. It doesn't seem usable for any other purpose. Kagi's business model relies almost entirely on user trust. Opting out in this manner would suggest a lack of trust, seems incongruent with using Kagi at all, and benefits no one.
All of this however, is an argument against the act of opting out itself. Counterintuitively, I think this option should be added. Seeing it as an option would give me as a user that much more confidence that I can control it if I deem it necessary, reinforcing user trust.
So the rather bizarre conclusion I arrive at is that I'd like to see it added, but also have no intention of using it.........weird.