Earlier quoted context omitted.
Thanks for the reply! My concern is with counting on people who do not search a lot to be a big part of your user base. Flat rate means those people might feel like they are overpaying, and if they leave you will start losing money on people who search a lot.
Being concerned is healthy, there are no worry free businesses.
Kagi at first seemed strategic with metered paid search, but choosing to go for growth and hoping most users will not search a lot feels like a downgrade from that.