Great question — answering as the UphillTech team:
The question is overstating its assertion that there are virtually no animated movies for adults. I could make a list but I'd rather address the underlying truth to your question, i.e. that there are proportionately less animated movies for adults, which I do think is true. First of all, if you're focusing on top-tier graphical quality, the production budget is not that far off from a live action movie. If a movie studio has the experience and equipment for making live action movies, it's easier (and presumably cheaper) to keep doing what you're doing instead of doing something completely new. CGI has become commonplace, but that's not the same as making an entire animated movie from the...
Full answer by Flater: https://movies.stackexchange.com/a/106503 (CC BY-SA 4.0).
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