Bartholow, B. D., Anderson, C. A., & Carnagey, N. L. (2005).
That study is nearly eight years old, probably the data was collected during the last ban? Likely well over twelve million AR rifles and an ungodly amount of commie rifles have been sold since that time in the US.
Most of the people I associate with are over 40 and nearly all of them hunt with ARs (the ones that hunt) of some description except when a shotgun or .22rf is called for.
I would say the days of Zumbo are either mostly behind us or in front of us. Still there is that perception based bias among some people out there.