That is correct. It’s an extension and as such a contribution from a Roon user, not an official thing by Roon:
Still, it costs like 3.49 IIRC and it’s helpful for some people.
Alternatively, use Airplay to cast Mac/iPad screen to Apple TV (or Chromecast with Android or from the Chrome browser), which is free and better for actually controlling Roon. Or any browser on the TV for the Now Playing screen.