You completely misunderstand. Windows and Mac are different enough from every linux distro that the argument isn't about them.
And if you're going to start talking about copy-rightable works of entertainment, then yes if you write a book based off another book just with 1 extra character (analogous to "install <major distro> and do apt install X") then that book would violate copyright and should not be written. It's the lack of copyright in FOSS that allows all the pointless duplication of effort with all the almost identical linux distros.
And if you're going to start talking about copy-rightable works of entertainment, then yes if you write a book based off another book just with 1 extra character (analogous to "install <major distro> and do apt install X") then that book would violate copyright and should not be written. It's the lack of copyright in FOSS that allows all the pointless duplication of effort with all the almost identical linux distros.