As a counterpoint, here's an amazing video making a convincing argument that "Uncanny Valley" isn't a thing:
The "Uncanny Valley" only exists in two dimensions.
In real life robots that look like "The Uncanny Valley" on the internet are fine.
Artists since they advertise in two dimensions use this 'trick'. But their work, like Ron Mueck's still looks cool IRL, it's just a different experience without the Uncanny Valley.
I'd like to know if anyone has actually made something that actually is the "Uncanny Valley" in 3 dimensions. I assume it's possible, but perhaps not. I'd be hard to advertise.
Perhaps you need to tap the part of the brain that extrapolates from 2 dimensions to 3 to get the horror.
The original Uncanny Valley hypothesis came out of robotics back in 1970, its application to computer graphics came decades later.
I don't even think 2D vs 3D plays much of a role, a realistic Luke Skywalker wax figure will look just as uncanny as CGI Luke in Mandalorian.
I find deepfakes interesting in this regard, as while they look much more realistic than most CGI, they never go uncanny. They can go a bit glitchy, blurry and might not look like a perfect replica of the faked person, but they still end up looking like person, not like an uncanny CGI copy.