I've played around with all of those levels at various points in school and my career. My knowledge of solid state physics mostly goes unused, mostly, but every other level is something I've had in mind at various points. I'd file them all under "good to know".

Sure, you can generally get by without low level knowledge, but it's nice knowing why certain design decisions were made. And as far as C goes, I think it's extremely useful to be familiar with how it translates to assembly, at least in general. It is knowledge that you will use regularly if you're programming in C in any significant capacity.

For example, reasoning about ABIs is something you'll have to do if you ever write a stable library interface. Reasoning about ABIs requires you to know the asm-level calling convention for the platform you're coding on.