Obviously they don't have the ancillary services (Maps etc), but for just searching, Kagi is far more likely to surface useful results instead of just the highest bidder. Compare a search like "us esta" for a clear demonstration.
I'm not entirely sure what "objectively superior" is even supposed to mean in the context of a search engine, or how this follows from having 50k users, but that ceases to be an even remotely plausible statement if you've ever attempted to get good non-English search results.
First search result for "us esta" in Google is "https://esta.cbp.dhs.gov/esta", same as in kagi, is that your objectivite fail at coming up with a simple metric?