This simply isn't true. The jump from Mac OS to Mac OS X was huge and Mac users ranted for years about it. You had different file structures, compatibility issu

This simply isn't true. The jump from Mac OS to Mac OS X was huge and Mac users ranted for years about it. You had different file structures, compatibility issues, and Mac OS Classic prided itself in its "out of your way, no nonsense" GUI while OS X started the "Fisher Price" GUI era. More than a decade has passed since then, so I don't remember all the details, but you certainly had to learn the OS X way, just like the man learning Windows 8.