>This is definitely a non-obvious behavior. Browsers historically were tied to their windows
Maybe in Windows, but as long as OS X has been around, and maybe in classic MacOS (Not sure, wasn't a user) applications have been uncoupled from their windows. Closing the last windows has never closed the application. This isn't surprising, and while it's not obvious, it's not like browser are doing something different than any other application.
In my opinion, this has always been a feature of MacOS. I can close the last window of an application without quitting the application (requiring startup again if I want to open another one).
Maybe in Windows, but as long as OS X has been around, and maybe in classic MacOS (Not sure, wasn't a user) applications have been uncoupled from their windows. Closing the last windows has never closed the application. This isn't surprising, and while it's not obvious, it's not like browser are doing something different than any other application.
In my opinion, this has always been a feature of MacOS. I can close the last window of an application without quitting the application (requiring startup again if I want to open another one).