I would paint it a gray to match the counter

Are u adding the 6” granite backsplash or removing (I see one section with it and one without). If you are keeping the short splash, then you don’t need the tiles. Can you remove them, patch any drywall that needs it and then paint? Paint same as rest of the kitchen?

Are you putting the 4 inch back on the rest of the counters, like some appear to have? If so, and you dont want to remove the rest of the backsplash, paint it the color of the walls, and let the 4 inch piece be your backsplash.

Agree you don’t need a backsplash; remove, sand and paint the same color as the walls. You should, however, finish installing the granite backsplash on the rest of the kitchen.

Thanks for the advice! Yes, we still finishing up the granite and will be adding the 4in granite back.