if kagi can make a search engine that charges users, why dont we have a 1$/month open source browser whose code can be verified but people pay to use monthly?

I guess that wouldn't really "open source" in the traditional sense, but that's clearly a tangent.

Personally, I'd love a paid for high quality browser that serves me rather than sneakily trying to get me to look at ads.

I think the challenge is that a browser is an incredibly difficult and large thing to build and maintain. So there aren't many wholly new browsers in existence, and therefore not very many business models being tried out.

Full agreement that I'd pay for such a thing- I have a browser and a terminal open non-stop during my workday. It's an important tool and I'd easily pay for a better offering if that was an option.

Would it be profitable without some heavy investments ?

https://kagi.com/stats

Paying to get a browser fork with less features? At that point, just pay $1 to Mozilla for firefox instead..