Let's consider them as market forces. Likes are internet currency. In that context dislikes are a secondary currency that doesn't have a clear value. Dislikes tend to depend on the content and current cultural norms to determine why the dislike was added. Their value is not easily determined. For a controversial creator a dislike may actually be a badge of honor. For a DIY creator it's a major negative. Due to this apparent ambiguity in the value of dislikes and what they mean I don't find them worth while.