During my really active yrs, say from 1975 to 1985 (classic content!), the number of injuries and death were low. My riding area at that time was Como St in Irvine CA. A couple of broken collarbones among the guys that I raced with is the worse I can remember.
Contrast this to the last 10 yrs, and the increase in injuries can't just be tied to cell phone use. In the Westwood CA area, we've had 3 or 4 deaths, several near deaths, 3 broken backs, numerous collabones (myself included), etc. In my mind, there is more to the equation than the increase in traffic.
One of the factors may be, simply, who gets on a bike nowadays. When I see triathlete types riding in traffic as though they are on some sort of closed TT course, I hope for their safety. I don't want to single them out, not at all. A lot of new, modern day racers have no clue as to how to deal with traffic. Whereas when I started, we just rode bicycles, some of these new guys go straight the "racer" category and end up getting in trouble.
As a coach of this sport, one of the things I try to teach is how to ride in traffic. Forget the HRMs, SRMs, blah blah blah......just don't get hit.
Wes Oishi
Los Angeles