"Roon Ready" versus "Chromecast built-in"?

Yes, that seems to be the main limitation.

Could you say more about that? Are you talking about some metadata flags that the device is supposed to implement?

Interesting. Wonder why they bother with it, then?

Interesting, I don’t see that in my setup.

Yes, there was some kind of bug, but I understand that has been fixed. Should test it.