I've seen Cats in its Broadway run, as a teenager. And I remember nothing about it, nothing, except the sense of crawling discomfort when one of the cats looked directly at me. (I seem to remember them coming out into the audience, but that might have been a fever dream I had a few nights later?)
And frankly, that wasn't the Uncanny Valley. The cats on stage weren't terrifying to look at, just weirdly disinhibited. Someone upthread had their finger on why these CG creations are so deep in the valley. They're not humans dressed as cats, and they're not anthropomorphic cats, neither of which would be discombobulating. They're just the wrong mix of traits of both. Human cranial structure, but with the ears moved to the top of the head. Naked human bodies with a thin covering of CG fur, with boobs and butts but no genitals or nipples. It's all so ... confusing.
that said, I'm not inherently opposed. A weird, uncomfortable but catchy body horror musical might be just what 2019 needs.