and who has only shot digital?
I was shooting film in 1967
And so was I.
I'd guess that anyone over 40 started shooting with film cameras, but only the wealthiest ones had SLRs. Even back in 1967 a film SLR was pretty expensive. At least for a young person. And remember, only very young people from 1967 would still be alive today! All of the "over 40 year olds" back then are over 90 or gone today.
I think most of us started shooting with P&S film cameras, then some of us moved up to film SLRs, and then those of us who were still are into photography by 2000 or so got digital cameras.
Anyone under 40 probably didn't "start with a film camera" although some may be using them today for artistic, style or nostalgia reasons.