There's nothing wrong with voting for yourself. The issue is that we don't want to reward self-upvotes unless there is enough support verifying that vote. We don't want to reward people that do lazy one comments and then upvote themselves behind the scenes. We also don't want huge whales voting for themselves without a significant community to back them up as well.
So for prominent YouTubers, if they bring an audience, they should be rewarded, but if the community can not match their vote in magnitude, they shouldn't be rewarded. The same goes for their commenters as well.
Very much a case by case basis. I do see what you mean.