There was also a discussion here:
It's too vague to seriously be considered as a law. I guess compiling MS-DOS after 2027 is illegal in California?! That's a "general purpose OS" with no concept of users.
If they reword it so it targets "consumer devices" and "commercial" OSes - then the law would make more sense. But right now, it's overreaching:
Operating System Providers: An operating system provider is a person or entity that develops, licenses, or controls the operating system software on a computer, mobile device, or any other general-purpose computing device.