I have been buying white cars forever. Plastic and metal just do not show the same colors no matter who makes them or who supplies the paint, just the way it is with water based paints. My Mercedes is very similar. This is not a mismatch of paint.
Go back in time to oil based paints and now we are talking, my 1996 Mercedes SL has almost no perceptible color difference between the plastic bumper cover and the metal of the car.
Never really noticed it though but here you can see mine is similar as well as everybody else's. Really depends on the lighting as to how noticeable it is.