Well, a) is a given, everyone cares about load times, even those that dont have the technical competency to name the phenomenon. And for me, personally, I guess its b and c. I am blind, so I do care about accessibility. However, I am also a old-time Linux command-line guy, from the 90s. I actually like Lynx, the load time and the simplicity, and the resource usage. If in my world a site could load in lynx (its all just about text) and it doesn't because of silly javascript framework, a kitten gets skinned and dies a horrible death.