From what I understood, he simply endorsed the film to help it get a wider audience. He didn't produce, direct, or have an involvement with the making of the film. That's what I meant.

Producers, executive or otherwise, are usually involved in financing the film before and during its production. This didn't happen. He saw it after production and felt compelled to help spread the message.

I think it's great that he did, but it's surely one of those weird artefacts of why Koyaanisqatsi is successful.