Notes:

For reference's sake, in previous games pokemon storage boxes had random backgrounds you could customize at will just for flavor purposes.

For example, here are all the available box BGs in Pokemon Platinum:

From Let's Go onward, it seems the series will follow suit with the "simplified UI" set by Pokebank and the Nintendo Switch and start excluding the feature from now on. And while one could argue it's too early to tell, I do wonder why would GAMEFREAK deliberately share an image of the storage box interface with a blank BG when the default setting has always been the grass/forest one.

Not a dealbreaker, but it's a shame to see it go.