>> And when that time comes, what will be the point of doing a 3d animation that looks live action

In a perverse way, economics.

Your stars will never age; they will always be young and beautiful and handsome and capable of doing their own stunts and easy to costume because they'll never gain or lose weight.

The Japanese figured this out years ago when they introduced the first totally CG newscaster. She was a huge hit, not only because she was easy on the eyes but she was easy to license for other uses, like posters and cel phone wallpapers and ads for fast food and perfume. Her union never complained that she was being overworked, because she had no union. She was always on time, knew her lines, never required more than a single take for a commercial. She never got into any scandals. She was, bottom line, the perfect employee.

That is why Hollywood is so fascinated with photorealistic CG characters.

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