Another explanation to consider is that older cyclists have had the opportunity to ride frames made out of various materials over the years and have gravitated towards Ti due to its superior ride quality / frame characteristics. I have owned Al frames, steel frames and Ti frames and althouch I have never owned a CF frame and I have rented several higher end CF bike (Trek Madone / Cervelo etc. ) for week long vacations and gotten in 5 + rides on each of the rentals. My ranking would be Ti 1st with steel a very close second (I have a nice Serotta CDA that I really enjoy riding). CF would be 3rd and Al last. To be honest I have not ruled out a CF frame and suspect I just have not found the right frame for me but doubt the addition of a CF bike to my stable would ever surpass my Ti ride as my go to bike.