Interesting point. I didn't give it that much thought since there are more relevant things to consider like the fact that Obama throws like a girl.
It would be difficult to quantify and account for the fact that some parents might have forbidden Elvis. A survey perhaps - but what would be the parameters? But, the purchasing power issue would indeed by subject to a legitimate estimate that could be incorporated into a model. That coefficient would make an enormous difference for comparison purposes.
To take it a step further, one might also try and accommodate differences in the overall number of choices available as well. I mean, if Elvis is 1 of 50 and Jackson 1 of 100 artists that might also make a difference due to level of competition. Actually this is a fun thought exercise. Look forward to your additional feedback.
I was talking to a friend who was an Elvis fan. She reminded me that it was a luxury to have a record player in the early years and stereo didn’t even exist! They listened to the radio, but at night the station reduced power and the static got too bad to listen, LOL.