I will never, ever understand the mentality of the whole "it's what the director approved, so it's how it should be" crowd.
No. A thousand times no.
If you come into an art gallery and buy an oil painting of mine because it really speaks to you, you hang it on your wall, you admire it every day, you know every inch of its surface, every brush stroke, and then almost 40 years later I walk into your home, take a permanent marker draw over the outlines, and completely recolour it with some Warhammer paints to smooth out any brush strokes, and tell you "it's what I always wanted it to be", is that the painting you fell in love with? Would you have bought it in the first place had it looked this way? Should you just accept it and love it because I'm the artist and I retroactively dictate how you get to enjoying it?
Yea, older versions of 'Aliens' don't disappear on physical media (and thankfully I have almost every release)- but we are entering an age of digital media, where physical is being phased out. The Aliens I had purchased on iTunes that I enjoy via Apple TV when I'm working away (which itself had awful colour grading as it was the blu-ray version, but was still nice enough quality to enjoy) I woke up to find had disappeared and been replaced with this crap. I didn't buy this. I didn't ask for this, and I wouldn't have paid for this. This isn't ok. Apple is only able to put out the version the studio wants on there.
More to the point, if this really is how James Cameron *really* wanted the movie to look in 1986, a teal and turquoise, oversharpened, waxy mess, then this just furthers the argument that sometimes directors simply don't deserve the credit they get, if the art they produce is actually just a byproduct of what they consider 'limitations of the time'. (And to be fair, grain aside, he was more than capable of using turquoise lighting in 1986, he chose deep blues, purples, and scarlets. Its revisionism whichever way you look at it)