Swearing isn't allowed here because it's a family friendly forum so sometimes there are kids here who read what we type. I don't think it's unreasonable for the mods to want to keep this forum free of drama and swearing.
Whether he told everyone or just one person that he wishes their animals would die- it's a completely unacceptable and rude thing to say. If you don't see what's wrong with that statement then this might not be the forum for you.