I get furries (well, enough for the purposes of this conversation at least), but they are different than "therians" right? I'm not as familiar with the term but it seems that they are people who identify as an animal not with.

The issue I have is that the wording here is pretty handwavy

This is pretty clearly a social and psychological phenomenon, not a neurological trait having nothing to do with a system of neurological development (influenced by hormones, for example).

I'm not so sure it's quite so "clear" to anyone that doesn't study these topics in detail. And I don't know enough about what is or is not a neurological trait.

To the best of our knowledge, hormones don’t influence the animals you like or identify with.

That's a good point. But the brain does and the brain is an organ as Steve points out. Is the difference of one being influenced by hormones sufficient?

That's the hair I'm trying to split.