It’s pretty obviously a dumb joke.

Even if it was completely serious, it just becomes a dumb statement. Its just showing how everything can be reworded to be presented as a binary choice like this. It doesn’t actually say anything bad about people for identifying any sort of way.

For example, there are a lot of species birds, but they can all be described by the binary choices of: Is Crow, or Not Crow. Still, its very obvious to anyone with a brain that that’s not the most helpful way to classify things.