Where would you find these metrics? Looking at the federated timeline, I see posts appearing at a pretty fast rate (more than one per second), though most of them are in Japanese.
It's very popular in Japan because of the "lolicon" phenomenon (cultural sexy drawings of youth people), which is not accepted by Twitter because of the occidental culture in which this is a taboo.
I bet that few of them will reply that it is an extinct animal, some others that it is a cool band, and most of them that they have never heard of such a thing.