I think most people don't understand the fact that Kagi is meta-search engine which literally collect the results of other search engines and display it and add very small amount of results from their index(tecilis).
People basically pay them to search Yandex and Brave for them.
You're enticing that they 'do very little'. But they do search multiple sources at once, providing a better choice of results for their users in addition to allowing users further customizable filters. If they're doing this then they're doing more than just the standard 'Yandex/Brave' search as you describe.
I do however, agree that they should state that they are a metasearch engine if that is their case. Also just seen their pricing - ludicrous!
So far so good! Have tested the system for a little while now, and have not been able to run into the same issues as before - so this might have solved the issues I've been having. While Ubuntu is not my first choice of distro, I will choose it any time of the day over Windows!