I would like to point out you CAN actually go buy trophies that say world's greatest artist. Not that it would mean much to the world on a grander scale.

That joke aside I believe you are right and it was something that was an issue on twitch a few years ago with view bots. But if we are decentralized then there is little that can be done at this moment. The blockchain doesn't have an anti-fraud purpose and it would have to be monitored for outside of the blockchain itself since the voting can be purchased with any other currency. I would argue that some values could be changed. Something like reputation taking more effect but then that could be manipulated as well if not implemented carefully.

It will be interesting to see how it all plays out.