Linus never used CVS because he couldn't stand it. The kernel had no version control until BitKeeper came along specifically because Linus wasn't sold on version control until he discovered BitKeeper, and then when McVoy killed their licenses, Linus chose to write his own system because he didn't like any of the existing ones.
BitKeeper was a totally new solution to a very old problem that was "solved" years ago. It was created by an "old guy" who knew the wheel had a large flat spot and figured out how to make it round. It was subsequently adopted by another "old guy" (Linus) who refused to use wheels with flat spots.
[1] https://en.wikipedia.org/wiki/Larry_McVoy
[2] https://en.wikipedia.org/wiki/Source_Code_Control_System