One of the big theories behind this movie is that the reason it even began to be made in the first place was Phoenix's ego and feeling he hadn't "done everything" with the role (also likely a factor in the singing being added), as Phillips pretty hardly said it was standalone for a long time after it came out.

Which really lends credit to the idea that this entire project wasn't Phillips himself trying to dab on fans, but a lot of higher powers themselves forcing it. Not to absolve him entirely of course.