Tiny Kagi has already shown an ability to produce better results than massive Google, despite them both dealing with the same SEO site gaming/structuring. Which is the reverse of what would be expected if Google's greater resources were also focused on quality.

Kagi already dodges the SEO bullet.

Disclaimer: I pay for Kagi. You should too!

With Kagi’s customers being users, not advertisers, they can put in features to mitigate against problems caused by SEO, like how Kagi bundles up all the “Top X abcdefg” lists that turned Google into trash.

This seems like a problem of the search space rather than solely Google's. How are you supposed to guard a system which, by its nature, provides financial incentive to others to game it?

No matter what weights and checks are put in place, some observers will notice how their rankings change and make appropriate modifications.

This isn't solved by Kagi's product, either. I'm a happy user and use it as my daily driver. That doesn't mean that, if it increases in popularity, the results will remain unskewed.