$10/m is unlimited searches though...
And yeah, searches are actually quite expensive. There's a LOT of infrastructure that goes into making something unique with your own search engine that isn't just a wrapper over Google.
The actual compute cost per search, in 2024, was $0.0125. Kagi states they want to keep Costa below $0.015 per search, but their search partners are a major expense.
That ofc ignores all the supporting infra, devs, support....etc that goes into making it all possible.