Non-RAAT functionality (Sonos, Squeezebox, Linn, AirPlay...)

Is there a definitive post on here about the device feature support of non-RAAT protocols?
i.e. whether things like volume control, play/pause, next, previous, etc controls work from devices that are using protocols such as Sonos streaming, Linn streaming, Squeezebox streaming, etc (maybe AirPlay too) with Roon?

For example, others have noted that changing the volume on a Sonos endpoint (either using the physical controls or the Sonos app) is not reflected in the Roon UI. I recently tested this on two Sonos PLAY:1s, one an original, and one a newer, second generation (I think model number A201, so the same internals as a Sonos One, but actually a PLAY:1 — see e.g. Both connected to Roon and play audio, but using the volume controls on the second generation model did update Roon, whereas the original model didn’t.

I also have a Squeezebox Radio, using it with Squeezebox streaming via Roon. I actually haven’t used it in a while now, but I also recall there not all the transport controls worked (I think also volume is not reflect in Roon?).

Anyway, while I understand all non-RAAT protocols are “second class citizens”, it would be good to know the state of their expected feature set with device controls/original first-party apps.

Squeezebox reflects volume always has on my units. Play pause and skip will work. Chromecast same functionality on my JBL link volume play/pause skip all are two way. Sonos arc is the same. Can’t vouch for the rest as dont use them but I imagine it’s the same basic functionality.

Oh, interesting, I will have to re-test my SB Radio. Sonos Arc is a “new” Sonos device, like my second gen PLAY:1 I suppose.