I say that no because, well, it's like if there was a huge fandom on Spongebob or something, which is not as bad. However, I do acknowledge that some bronies are also furries, therefore creating a brony subset of the furry fandom and vice-versa. Otherwise I guess it's 2 different things.
Think of a Venn diagram, one side being the bronies and the other being the furries.