It takes a really long time to learn complex systems. I’ve been using Windows since 1986 and I still discover new things about it all the time. And I already know absurdly-vast amounts about the OS and its underpinnings.

And I’ve been using the modern version (BSD-based) of Mac OS since 2014 and I learn things about it daily. Anyone who claims you can master a complex system in a few months is lying. It’s just not possible, not even those of us far to the right on the IQ curve.