The web store ecosystem is atrocious. You cannot rely on Google's browser services to make money. They will randomly take down your extension for a ~month in response to malformed (i.e. invalid and illegal) DMCA notices, and they barely maintain the developer tools - I've watched key parts of the developer dashboard break and go unfixed for months even after reporting them.

If you want to do this stuff you have to do it all from scratch and hope Google doesn't decide to get mad at you.

They also make it very hard to push updates promptly which means if a major bug or security issue is found it can take multiple days for users to get a fix, so you end up having to find your own way to push updates (despite the fact that store policy sort of prohibits doing so).