Everyone.
If someone says not to upvote their post, don't upvote it.
I've seen posts that tell individuals not to upvote, most commonly vents, and they still have upvotes.
It's not hard to read the post and not upvote, or if you upvoted before reading the post, undo it.
In conslusion: If someone says not to upvote a post, don't do it.
Thank you for coming to my Ted talk.
/srs /nm