You may be right, strictly speaking, but the reality for me is that I really don't like a lot of what would be traditionally characterized as ‘rock’, although I very much appreciate its value. If I had to listen to CCR or, the Stones, or Chuck Berry, etc. for an extended period it would bore me, but that's obviously just me. For the record, I don't like most ‘heavy metal’.
Regarding your comment about musicianship, I agree that there are many out there who aren't technically proficient or innovative musicians, but many who are play music that you probably wouldn't consider Rock and Roll. For example, Steve Howe of Yes is an absolutely phenomenal guitarist, and Bill Bruford who played with Yes and King Crimson is a phenomenal drummer. Yes and Crimson were very innovative as well, but you either like their stuff, or you don't.
I agree. After you listen to him for awhile you can hear that what he is doing is amazing. But most people don’t like him and can’t appreciate his talent.