Popular Music? Fiction writing? Journalism? Creating video content would qualify. (Possibly relevant: YouTube's audience is mostly male, while Tumblr's is mostly female. IIRC, the audience for video pornography also tends to skew male, while written erotica skews female.)

The home computing revolution was a weird inflection point.

Basically, it's the start of when computing went from a tool for accounting/administration/bureaucracy to also broadly encompassing media. Many of the de-profesionalized fields I mention above are associated with media.

Again, part of my claim is: this is not really a surprising or weird argument. It's pretty obvious from the recent history of the field.

I do think you're onto something.