Right, I now have the hardware. It was a right faff getting everything to connect. The Chromecast needed updating, which was fine, then the controller needed an update. Fine. But for some reason the controller wouldn't connect to the CC, although it sounded like it had connected as I could hear I was controller Destiny, but I was being shown a screen to connect the controller to the CC. Rebooted the CC and then I could see what was going on, but the controller wasn't connecting. Rebooted the controller and then it connected. It's not helped by a strange black banner being overlaid on my Stadia app covering stuff in trying to do.
Right, cool all connected and working. For up Destiny 2 ....Server Offline. ***!