“I’m sure you’re perfectly nice as a friend, but I’m not looking for a friend. I like to keep my work and private life separate, and I’ll thank you to do the same around me. Don’t think I dislike you; but for me, personal chat is an unwelcome distraction.”
You know that the current voting system isn’t like/dislike, right? Or it’s not supposed to be. Your proposed system would have the same problem: users would use it as like / dislike buttons.