I don't think it's the aesthetics that people react to. The aesthetics are a little on the 1980s neon retro side, but personally, I find this almost creepily dissonant purely in how far the message is from the product. Nobody would deny that lots of people use Dropbox for "creative" work. But Dropbox itself has nothing to do with creativity -- there's no sense in which Dropbox itself can be a fun, zany, kinetic kind of experience. It's not GoPro. It's a folder that syncs. This design reeks of someone uncool trying to appeal to a young, fashion-conscious demographic, with cringeworthy results. It's as transparently cynical as any attempt Microsoft (for example) have ever made to appeal to anyone younger than 30.