For me, this line is key:
First, the news media — which wouldn’t understand that all that “Subscribe to PewDiePie” stuff was as much a joke as an actual endorsement — would accuse him of inspiring a mass murderer.
"Inner Youtube" as used by the author describes a place where context is necessary (the "UV sensitivity" he talks about). But the exclusivity of that context is what defines the place. If your parents were "in touch", the jokes cease to be funny, the community dilutes and the show's over. It's not just that the kids have become "UV sensitive" it's that they've become dependent on UV light to thrive.
One of the things every Youtube creator I've ever worked with has in common - and I've worked with some big names - is that no matter their level of Youtube fame, they'll gladly trade it all for a shot in the Real Machine. Subscribers and views are seen as the diluted markers of allegiance that they are- a SAG actor makes more from ten seconds as an extra than a Youtuber will make from ten million views. So they all want to rub against the real world, but they all know that if they rub too hard, they won't have that special UV coating any longer. So they're all left singing for their supper under rules that could change any moment as interpreted by popular opinion.