Unfortunately I feel like this statistic is simply pop culture still being pop culture. The movies Elvis, Rocketman, Queen (or whatever that one was named), the show Stranger Things, all feature older music. And let's face it that music was all pretty dang good. So I think its why this era of music is growing, and today's music generally speaking sucks. Though I do think your third paragraph also contributes.
Unfortunately I feel like this statistic is simply pop culture still being pop culture. The movies Elvis, Rocketman, Queen (or whatever that one was named), the show Stranger Things, all feature older music. And let's face it that music was all pretty dang good. So I think its why this era of music is growing, and today's music generally speaking sucks. Though I do think your third paragraph also contributes.