@Fido,
I think maybe you and I share a similar view of impressionist work.
I see the very same thing in Las Meninas as you have shared.
I like Van Gogh, not because he was very successful in his impressions, but because he understood the struggle to produce a successful impression.
I think too many failed impressions get lumped in and misunderstood, because the artist is impressionist.
A successful impressionist painting is very difficult to produce, and I don't know of anyone who has been more than marginally successful at it.
I believe the success depends largely upon the viewer having actually experienced the scene. If the viewer lacks the necessary reference, the impression fails.
My favorite Van Gogh is a man and his dog walking across a snowy field in early spring. Where I live, I have experienced such a day many times and I am intimately familiar with the light and nameless color of the scene.
This interdependency between the artist and the viewer is, IMO, the very soul of impressionism.