Don’t overthink it.
My skin, less my naturally abundant fur covering, is white. Most typically pale white around the middle, as I have abandoned the days of working shirtless outside. I’m not dark black, not FDE, not stainless, not purple... no color of gun matches my skin. Most commonly, I wear blue jeans, but have never owned a denim holster nor a mid-blue pistol or revolver... sure, we can speculate that phones are black and a small portion of the population remains nerdy enough to wear their phones on their belt, but the human eye catches contrast, and frankly, many of us will readily be caught by a belt-phone, considering, indeed, the owner is a ridiculous nerd for it... lump, bumps, contrasting colors, movement, all of it catches attention...
Keep your ass covered and nobody will see your ass...