they've just (as in yesterday, on Jan 5th) added a Lemmy/Kbin lens to their engine (meaning that it's easier to search specifically the Threadiverse):
Kagi is popular on Lemmy and a lot of Lemmy users are using Kagi. We have released the first version of a Lemmy/Kbin search lens
I don't really think they've been playing some kind of a long guerilla con of advertising here for half a year and then adding a feature that would make searching more convenient for their supposed covert marketing department.
and if they did, the Brave decision is about to backfire on them.