I listened to Andrew Collins' Film Music show on Classic FM last night here in the UK. It was a Nolan/Zimmer "special". Nolan stated that the cue we've heard thus far from DUNKIRK, he asked Zimmer not to make it too musical and for it to simply propel the action. I got the impression Collins wasn't too enamoured with it. A ticking motion...
From Tarantino's own lips: Morricone composed all his music for THE HATEFUL EIGHT based on only having read the script. He never saw the film before composing and, if I recall correctly, hadn't seen it by the time he recorded the score either.
Why is this even a question? Hans Zimmer has something singularly unique in the industry, which is his Remote Control Productions. It is a massive complex with a massive roster of musicians dedicated to churning out his projects. He bounces around from project to project doing high-level creative stuff and his team finishes the rest. It is all about scalability and has been so from the beginning. He willingly has made this trade off to be able to churn out volume. He is basically a PRODUCER.
No other composer has ever had these resources, except for early studio composers in the Golden Age, like Alfred Newman.
We're not talking about orchestrators and assistants for the composer here. Remote Control Productions is an efficient machine with a large staff. That's not a secret, so I don't know why it's always debated.
Same with Zimmer being a good composer. When he actually had to do all the work he was a decent composer. But now he's just a producer.