The primary reason why CGI is used is to save money. The secondary is to ease production of movies, which at the end saves money and time (which is money). Sty

The primary reason why CGI is used is to save money. The secondary is to ease production of movies, which at the end saves money and time (which is money). Styling as done in some of them is an optional bonus if creators strive for some additional artistic message, but otherwise its all about money, money, money. You even contradict yourself - they tried to look Avengers as realistically as possible within the realm of comic book fairy tale, that's why they changed character of Thanos significantly well after introducing him (arguably a good choice). From cartoonish styling to realism. Nobody would take the epic battles so seriously if they all looked like Ready Player One.