If you are using the Safe Area plugin, then most likely you want to support Android’s Edge-to-Edge feature which expands your app the the edges of the screen. In this case, you don’t set the background color as your app content is in that area. You just need to set the System Bar styles.
If you want to disable edge-to-edge, then take a look at Android Edge-to-Edge Support Plugin for Capacitor - Capawesome.
Reliable Edge-to-Edge in Ionic 8 and Capacitor 7 is also a good resource.