I don't feel the need to know every single setting or menu, but I do need to understand how to get the adjustments and controls quickly and correctly. I've never even tried to learn live view or video because I do not use it. I have read the entire manual a few times and when I go out to photograph I use the same functionality as I've been doing for over 30 years.
Talk about an inexpensive camera verses an expensive one, I do not look at menu's or fancy functions. I pay more for quality and photographic capabilities. I want my camera to withstand rain, cold, heat and perhaps hopefully survive a bit of a knock if it drops.
I hate menu driven controls for simple functionality such as shutter, aperture, ISO and other things that actually create the photo. I need these functions simple and straight forward.
With computers driving everything from our cars to our toasters, too many menu based functions add complications that you have no time for out in the field when working quickly with your camera.