Never heard of him.
It seems to me these people seriously overestimate the impact of classical music and musicians on the music scene today and the wider public in general.
But I think that's beside the point, because I don't think the premise is that people "should" have recognized Bell as a celebrity. The naive hope is rather that people can recognize great art when they encounter it.
The reaction after (presumably) hearing some of the video . . . shows that they're not going to.
Regardless of celebrity, a classically-trained violinist and a busker are two very different things. (Buskers have more charisma!)
How about they heard of the composers that he played the music of (Bach, Massenet, Schubert and Ponce), but not of the guy that played?
When I go and buy a Big Mac, I care that it's a Big Mac, not whether the cook that re-heated it today was Bob or Joe.
You're just in the 0.01% that would have stopped and listened, just like you're in the 0.01% that would buy his album or go to his concert.
My point is that classical music soloist is a niche hobby, just like my playing cards collection is a niche hobby, and that to expect that more than 0.01% of the world would stop on their way to work to look at my playing cards collection is simply laughable. This whole article is a joke.