The colour is different, but is it wrong?
Without access to original elements we can't really know what the film looked like in 1991. Even original prints would not be a "true" reflection as, by virtue of how they were made, there would be significant colour variance from print to print. Or even reel to reel in some cases. Only an original, unfaded, answer print would give a "true" idea of what the original timing was. That's before looking at variances in how a film would look projected.
The colour of the screen, the type of lamp-house on the projector, even the lens itself can alter the colour we saw in the cinema. For example projecting a vintage print using a (relatively) modern film projector, using halogen lamps rather than carbon arc lamps, would alter the colour temperature away from what it was originally. I remember reading about how David Lean was doing the final colour timing for the print used for premiere of the Lawrence of Arabia restoration at Odeon Marble Arch. He got it where he wanted it and then a technician came in and repainted the screen. Completely changing the look.
Using past home editions is never going to tell us anything other than what that version looked like. Especially when they use an older master. The master used for the previous T2 Blu-ray is, unless I'm mistaken (which is always a distinct possibility), the same one used for the 2003 WMV HD version. It is, by current standards, archaic. Using it discern what the film looked like in cinemas in 1991 is unwise.
Many of the comparison shots between different releases of films just show they are different. The Aliens shot posted above is very red in one shot and very blue/green in the other. Which is more correct to the original version is not really knowable without good reference. The Titanic shots are different, but which is more authentic to the 1997 original? Arguing one is more natural is to miss the point. Films have used unnatural colour to evoke meaning since the dawn of cinema. Again without good reference we can't judge which is more authentic to the original.
In any case human vision is quirky when it comes to colour. We are far more sensitive to contrast than colour. We have really bad colour memory. Our eyes adjust to new white points easily. Change the white point on your monitor and it will stick out at first, but you will soon get used to it and it will soon seem normal. The first time I properly calibrated my screen to D65 everything looked "wrong". But now it is normal. Now most screens which aren't mine look "wrong". But again, I soon adjust.
I guess my point is all we are really doing here is looking at whether we prefer the new grade or the old one. It may be entirely revisionist. It may be completely authentic (or at least as close as is possible when transferring film to 8 bit video). It may be that if we prefer the old one it is because it what we have become used to.
Or I could just be full of shit.