why would anyone pay for a browser when all the rest of them are free?
The browser that does not track you, does not report to Google or facebook, etc? That's why.
If it were possible to suppress all ads, then many people would happily sell you that solution. And the sites pushing those ads will see the money flowing to those people and not them, and so will grudgingly refuse to serve you any content.
As ad blockers get more popular and more effective, it's already happening more and more.
You can have a magical "don't show me ads" button only as long as it doesn't work very well. (And I have mine: Firefox + µBlock Origin.)
Call me a pessimist but I doubt this. Most people don't mind ads, and when you couple that with the vast number of free browser alternatives, I doubt so many people would pay (and even if they got some, I'd expect churn to be high too).
I think us “nerds” dramatically overvalue how important privacy is to the general public right now. Even ignoring the developing world, most people will agree that tracking is bad, but most will continue to use legacy browsers because they don’t think it’s 100/year bad. And the growing population of young and tech savvy people who are one Google away from installing uBlock Origin will not pay for your product either.
Not to mention —- even the proportion of HN readers can take other measures to approximate anti tracking anyways. uBlock Origin + Pihole + a good VPN is enough for even most of us (personally, it is enough for me).
uBlock Origin author specifically states he does not want donations or to sell licenses because he does not want to support the product at all - he wants to do what he wants and not what the "customers" or "donors" might want.