Vlogger runs into Keanu Reeves

You're not a void. That statement sums it up in my mind. I consider it an effect of "best <blank> ever!" Culture. Many media personalities or youtubers don't have the skill to emote (especially insincere emotion) or don't trust a mass audience to be intelligent enough to interpret subtlety. They use over the top expression to try and show how deeply they feel and evoke emotional response from viewers. Then viewers get conditioned to that as an emotional response and mimic it either sincerely or to increase credibility. People get used to the idea of these extremes so often will think anything less means disinterest- "why aren't you more excited? I just told you that ghost busters 2 is coming out with new box art and you didn't even flip a car or punch a rodeo clown!" People start to expect minor things to get major responses which means major things then need even more major responses and so on. More than anything while some naturally are exaggerated in response most are disingenuous.