I'm willing to bet there used to be a way to see more info about the picture currently on the backdrop screensaver through the google home app on the iphone.
I cant seem to find it any more.
Please tell me I'm not going crazy.
Edit: So after reading more and I came to the conclusion that its simply broken on the combination I have (Sony Bravia with Android TV). Also found this - https://www.reddit.com/r/AndroidTV/comments/7t8hje/backdrop_android_tv_vs_chromecast_default_screen/ - Which points towards more differences between "Backdrop" screensaver versions. I really wish google wouldn't do things this way. Why do I need to have that constant "Cast" note on my screensaver just cause I bought a Sony?!
Pretty sure the info you see varies by device. Home shows me lots of info for regular Chromecast dongles, but little (maybe nothing- I can't remember) for my androidtv device showing the Chromecast screensaver.