check the ratings for your self, it was heavily criticized for low production value and only had a 2.5 out of 5 starts in many Japanese movie reviews, lot's of westerners also didn't like it for the same reasons.
like here's an exert from Wikipedia.
The movie has received intense criticism from fans of the Attack on Titan manga and anime series for taking creative liberties from the source material. Kotaku said "The First Attack on Titan Movie Stinks".[31] SFX artist Yoshihiro Nishimura and director Shinji Higuchi responded to some critics, with Nishimura calling out critics who have criticized the film's special effects for not living up to the standards of Hollywood effects, stating, "I’m sorry, but deciding what movies to see based on their budget, and comparing everything to Hollywood, that’s like how some people feel secure buying Okame natto when they go to the supermarket", while one critic who criticized the characters in the film made Higuchi reply, "who’s the idiot who gave this guy an early release of the film?!