I use Kagi as my search engine, and GNU/Linux for my operating system. I think both people who use each of these like recommending them to people for the same reason: like like using it, and the greatest danger to not being able to use it is if no one else does, as that would cause it to cease. People recommend it because they genuinely think other people would enjoy it, but also selfishly because they want to continue to use it themselves.

I would interpret "authentic" here to mean that they are coming from real and authentic HN users who happens to be kagi users. The intersection is probably high enough.

A lot of HNers would have very positive views and comments about any particular thing, which does not mean they are associated with them.

I have multiple comments on HN, Reddit, and Lemmy recommending Kagi with effusive praise and apologizing for sounding like a paid ad.