After 50 years of Unix/Linux it is STILL not “user-friendly” enough to where grandma can install it on her machine to see email pictures of her grandkids.
Until it is, it will never be mainstream.
Even though it is technically a superior operating system.
And I know what I am talking about. I do Windows GUI and device drivers AND ALSO Linux embedded systems FOR A LIVING.
Grandma can't install Windows, either.