You or I can use Linux, because we're the same type of people who visit Hacker News. It's also completely possible to get your great-grandma on Linux, since the web browsers work the same and you can install the specific apps they need to use and they'll never care about anything else. But the middle user is working in an office exchanging Microsoft Office documents all day, making video calls through Teams, and using one out of a zillion business apps developed specifically for Windows.
We need more free and good projects, and the problem is, that costs time, and in between Richard Stallman's heyday and now, the rent's quadrupled.