I think you vastly overestimate the skills that are necessary for most jobs. Also, it should be noted that Amazon and Google don't interview for specific jobs

I think you vastly overestimate the skills that are necessary for most jobs. Also, it should be noted that Amazon and Google don't interview for specific jobs -- they interview you for a job at the company and then you get placed. That would imply that at least at Google and Amazon, the skills are transferable across everything they do.