On Corridor Crew’s latest vfx artists react they talked about this movie.

Basically it was supposed to be a different style movie and then executives got involved wanting it to appeal to a larger audience causing a bunch of re-editing. And the special effects were basically placeholders from the original version of the movie reused as final assests in the executives ‘wide market’ version.

They also go into how some morally questionable stock footage is used in it as well.