You might be right, but the next question is fashion. Will the same fonts be used still in 5 years, or (more likely) the new hotness will arrive? Should the browsers update the list each year? Then some fonts that were available will suddenly be not? Not so great.
Web standards and browser features are generally built for the long term and backward compatibility. I mean, it's not impossible to find a solution, but it's definitely not "let's download some fonts and bundle with the browser, done" kind of problem.
When you control 70% of the desktop market share, and you are releasing an evergreen browser that updates weekly, if not more frequently, any argument about not being able to stay on top of changes in the environment become rather silly.
Web standards and browser features are generally built for the long term and backward compatibility. I mean, it's not impossible to find a solution, but it's definitely not "let's download some fonts and bundle with the browser, done" kind of problem.