Switch your screensaver over to an app called Photo Gallery and Screensaver. You can get the same images but also better control of Google photos if you use that and as a bonus you can get those nice Apple TV moving ones too.
It's paid but I was fed up of the default one and don't regret buying it at all.
I choose Aerial Dream.
https://play.google.com/store/apps/details?id=com.codingbuffalo.aerialdream&hl=en
It takes Apple TV Screensaver and put it on android.
I hate it so much. I’ve been tempted to plug my gen 1 chromecast into my xiaomi Android tv just to have the “normal” background with weather or whatever
If you're using Android TV, you can replace that screen with Dreamy, which is a billion times more customizable with image categories and all, and you can still chromecast.
I'm using this as my screen saver
Aerial Dream and Dreamy from the Play Store are great and both are free,
Use a different screensaver
I am using "fotoo" free version, it has 5 minute pauses occasionally but its ok, you need to start app because screensaver option works only in full version.
Use a different screensaver? Google makes it easy. You can even get Aerial (AppleTV screensaver)... Now if you want to remove from Backdrop:
You will probably need to edit the Backdrop apk and then sideload it to your device. This will take some knowledge on the process but if you're determined you can learn it fast enough.
Is there a Flickr Screensaver for Android TV? Thats my favorite on my gen3 appletv
I use the clock as my screensaver.
I looked that up my self when i first got my Tv cause i am use to using my chrome cast.. as far as what i have read you can not remove it.
I really wish google worked over these screensavers.
The million dollar question!
As far as I know, you can't :(