SearXNG is different though, because it still relies on a data-harvesting, ad-driven online economy. Off course if all you care about is privacy, might be fine, not sure how good it is at hiding you, but if you care more about not having your data/attention be the revenue source and having software incentives be to offer something customers are willing to part money for, Kagi is still it.

As I remember, Kagi's index isn't entirely its own. They do some crawling themselves, but they still rely heavily on purchasing search results from Microsoft and Google to complement their own.

That's true, that's a money constraint, which hopefully would mean as they gain more paying users, they can scale their index further, and rely less and less on other indexes.