[rapind]

I think it's obvious enough without getting into the weeds like this unless their sample size is unreasonably small. E-book yes obviously counts. For the rest, like fanfic? Probably, but does it matter here? Is this actually going to move the needle?

[pessimizer]

Be cool if they would research that, instead of asking rhetorical questions and assuming that none of it matters and everything is "obvious."

I think it's just people being snooty. Bestsellers are trash, and by definition a plurality of readers are reading them. I don't think someone who reads Gladwell has any greater cognitive power than somebody who reads twitter.