There are various protocols for TVs to cast things, it seems like this one uses DIAL, whereas CATT uses Google Cast. I was thrown off by the icon, it does seem like the two are slightly different, thanks for the correction.
FWIW I didn't know about CATT, and I actually have some use for it. I sometimes want to cast local video files from my PC to a projector on the other side of the room. That already has a Chromecast so CATT should make it easy.