To imply that the reason for this action was racially influenced is pretty much beyond a joke for me. I've seen literally zero evidence that the witnesses are doing this for anything related to a racial reason.
The closest thing I've seen to it, and it's not exactly racism, IMO, was Bernie's comments regarding Justin and communism, presumably because Justin was born in a communist ideology and could theoretically be influenced by that. But considering just how many outrageous claims Bernie makes when he's upset, I'm unable to conclude for sure that he even really believes that.
And on personal level, I happen to like most Chinese people I've met, and the majority of my social interactions outside of work are with Chinese people, since my hobby is table tennis. I've even been studying Mandarin for the past few years, in my spare time, so I'm able to communicate better with some of my Chinese friends who don't speak English.
Finally, to answer your thought question, I would certainly have acted the same way with your hypothetical Stanford graduate. I can't answer with certainty for others, of course, but if he had the same history and taken the same actions as Justin has, I believe there would be no difference in the reaction.