The same was true in Harry Potter where they could have built a CGI castle, but instead built a huge model along with some painstaking miniature sets which they could fly a camera through and then composite the transitions into the live sets. The animatronic Hippogriff used “Prisoner of Azkaban” can be seen on the studio tour and it’s “waking up” sequence would have you believe you were looking at a real creature. PoA was released in 2004, Pixar only got fur right with Monsters Inc in 2001, so odds are that a CGI Hippogriff would have looked far inferior to a model made with real feathers.
These days, costs have come down and you see bad CGI everywhere because everyone can “have a go”. Unfortunately, even big budget movies animated by professionals have a lot of shortcomings because CGI is now used as a shortcut. Directors demand scenes be knocked out quickly and cheaply, refusing to pay for the artists to devote the same care and attention to their digital work as miniaturists would have been allowed to devote to their models. Where HP, LoTR or JP built elaborate sets and just used CGI to augment the “impossible” bits, The Hobbit and Jurassic World just film in front of a big blue screen and build the entire scene in a computer, which inevitably won’t be as detailed as real life or stand up to detailed scrutiny.