But does it surface relevant search results?

Many things on the web use Yandex.

Its funny because Kagi apparently also uses Google, and Microsoft and other threads were complaining about it.

It sounds like they use everything to give their subscribers good results. Which is what it sounds like I am paying for.

What's your point? Yandex is quite a competent search engine

I use a great number of russian sites, mostly when I want to download textbooks, audiobooks, etc.

Yandex is great if youre searching for pirated content or for DMCA'd content that ended up on Gitflic.ru

Anti-drm tools are a big case in point. And so is Bypass Paywalls Clean Firefox plugin. All of these have been purged from the "Great American Corporate Firewall".

Russian people != Russian govt != Russian companies.

I just use the tools that work.