Totally agree - I think the main issue with Kagi is that although they have clearly built out the service and are offering it for free at the moment, their premise that people will
actually micropay for a search hasn't been tested yet.
It's easy to get users if you offer a paid service for free, but much more difficult to get people to pay for it.
(They have done surveys where people have said they would pay, but this is different to actually putting their credit card in and putting their money where their mouths are!)