In my opinion, it looks like the reality is in between. The film has definitely been brightened to have more midrange, probably just due to the overall yellow-shift bringing detail out in the shadows that was previously less visible because of the former blue-shift, as blue eats up detail and yellow reveals it. Many examples in the pics look much more natural on the blu-ray, like some of classroom scenes. Many of the Cairo scenes are yellower and look nice, while the older version is a bit blue-shifted and may have just been a choice on the part of the colorist or even Spielberg, as the difference is subtle without the side-by-side comparison, it would be hard to notice if you were just watching the film. However, it seems clear to me that the DVD also has instances that are likely to be truer to how the film originally looked. If the sky is visible and the scene looks natural in the older timing it would suprising if it was actually originally supposed to be blown out and with a less natural overall look to the colour and contrast. The shots from the opening as well seem more natural with the bluer and more low-key look seen on the DVD. That shot digging up the well of souls looks like it has had the saturation pumped up, but that shot was a matte composite which dilutes the colours, so the blu-ray may actually be closer to how the elements were original shot and meant to be seen as. Sadly, the prints I've seen have always been a bit pink-shifted so it's a tough call, and I can't remember details that specific just from memory. If someone had a print that could be examined in detail you could probably tell even if there was fading going on.