[freediver]

Kagi's ranking algorithm is already public. Kagi downranks sites with ads/trackers and promotes sites that do not have them.

The motive people manipulate Google is financial gain, most commonly monetizing traffic with ads/affiliate links.

That does not work for Kagi, first because there is no financial gain, second the amount of traffic you would get would be a fraction you would get from Google and that is not going to change any time soon.

Not saying it is immune to manipulation, I would love to know what a good attack vector and motivation behind it would be.