Having 9.5 million subscribers on a science-based YouTube channel is definitely more notable than having gone to university, or indeed having a PhD. I think the writer picked the correct description here.
It's no wonder anti-vaccine material is so widespread. Someone famous on Youtube said it was bad, it must be true!
I'd suggest that very few YouTubers are popular because they are popular, in fact I think this is fairly rare in general. I think it's more likely that they provide some value to their audiences. I think looking down on "celebrity culture" often fails to account for the types of value that one doesn't value themselves.
I totally get that you value Gig Hadid’s opinion on wardrobe whereas I don’t, nor do I judge, to each his/her own. But, to claim that her opinion is more accurate/better/truthful to that of a respected fashion designer or industry expert is inherently flawed. Wearing clothes is not the same as designing them.
If I asked you who Woodrow Wilson was, what would you respond with?
A better example would be Brian May (of Queen). No correlation between academic credentials and artistic career. There, if the article were about black holes and May had an opinion, I would expect the reporter to cite his PhD, making it a (potentially) informed opinion.
> A better example would be Brian May (of Queen). No correlation between academic credentials and artistic career
I am not sure why that example is better -- Muller's academic credentials are very well related to his career. As were Wilson's.