I don't believe that's the true problem. Booting operating system is not a problem. There's no standardized hardware abstraction layer in PC either, every OS brings their own set of drivers.

My guess is that modern hardware is too complicated for one hacker to write reliable drivers. That wasn't the case back in the 90-s, when Linux matured. So we are at mercy of hardware manufacturers and they happened to not be interested in open upstreamed drivers.