iOS Screen Time - Can't turn off sync across child's multiple devices

My daughter has had an iPad for a number of years and we've had Screen Time turned on without too many issues. Today we got her an iPhone and even though I've turned off "Share Across Devices" on both devices, I can't get them to quit syncing settings across both.

I want to have a different set of settings on each device, turning off "Share Across Devices" should be the fix. I've called Apple and was told by a Senior Advisor that she thought Apple wants it to work this way that it syncs....what?! Why have the toggle then? If the toggle is there it should function.

Both devices are up to date on 17.6.1

Can anyone PLEASE confirm that they are successful at setting different Screen Time settings for their child's multiple devices??