I've been thinking the same thing every time I jump in or out of the newer cockpits to or from the older ones. Every single time.
The difference in quality of design and details is quite massive - and almost jarring at times. Even the textures look better now. So, I don't know if the the art team changed, got better at their job, or just adjusted their standards to the capacity of new hardwares, but anyway, I would indeed love them to go over the old cockpits sometimes and redesign these, or at least refresh the uglier textures.
Unfortunately, I don't think it's gonna happen any time soon. If it ever gets into their to-do list the priority must be so low it might as well not be worth thinking about. I wouldn't hold my breath.