The whole pastel palette is great. The calm colors and (in the case of real clothing) curious yet uniform texture tickles the autism in all the right spots. As for gray itself, it's among the calmest of the palette. It's also symbolically satisfying that it's between black and white.
Imagine an alien sharing a cool human fact they just learned like ”hey guys did you know that the silvery markings on humans actually aren’t true stripes? They’re called stretch marks, they happen when the human is growing fast enough to actually outgrow their skin, which is apparently something that just fucking happens to almost all of them at some point of their life.”
and another one is like ”wait so you’re saying humans don’t have stripes.”
”actually they do, but the stripes are invisible. There’s genetic code that’d give them stripes but they’re just the same colour as the rest of the skin. So the visible stripes are not real stripes and the real stripes are invisible.”
”I swear if you tell me one more weird human thing today I’m beating your ass.”