Consumers spent about $47b in revenue on the Play Store, of that Google keeps about 30% so that’s $14b. Google’s total revenue is $306 billion, so the Play Store generates only 5% of Google’s total revenue.
We don’t know how much Android costs Google. They have to develop the OS and maintain it, they have to develop all the android apps. They have to run the servers that handle the traffic from the apps, and so-on.
We used web browsers just fine before Chrome existed
Between 1999 when Netscape was acquired by AOL and when Chrome was launched in 2008, Internet Explorer absolutely dominated browser user share.
before even Google existed, and nobody was paying $79.99 for them
No, but Netscape had planned to start charging for their browser, until Microsoft drove them out of business by bundling IE for free with Windows, illegally leveraging their monopoly to drive the company out of business. Microsoft was willing to give away IE for free because they thought it was strategically important to control the Internet, and were willing to take a huge loss on the browser business to do that. They used the money from Office / Windows to subsidize their free browser, which was illegal.