I understand the need for having one particular defined name for a species, honestly. That makes some sense to me. But just because taxonomically a bird is not called a seagull doesn’t mean that it is not a seagull. Otherwise what is a seagull? There is no bird that has the ‘official’ name “seagull”. So what, seagulls don’t exist? It’s a semantic distinction that is meaningless outside of its narrow context.