Browser in those days, is not a good business. IE6 sticks years no updates, watching Firefox or Chrome grab the market, because Microsoft do not gain 1 cent from browser software, they were waiting for Google's bad luck. Until a decade later, everybody saw browser's value.
I don"t think any business has made money on building and supplying a browser.
So they have to get the money back from somewhere.
Google from getting you to use other google things and getting more advertising revenue.
MS by making you use Windows (yes IE was available for the Mac but I think that was to keep Apple afloat to stop anti-trust problems).
Apple first to get out of IE and then to get a browser on iOS and then not have to use Chrome and now get paid by Google to use its search engine. Possibly blocking Flash also was a reason.
Netscape - well that is the problem where do they get revenue - Google paying them to be the default search and probably to head off anti-trust.
