For the most part the movie made me feel quite uneasy. I wrote up the bulk of the reasons why on Facebook shortly after watching it months ago, and can't be bothered retreading all the fine points, but for the most part the thing feels too disingenuous and starry-eyed for me to take seriously. The one small section where you have Rupert Neve actually laying down some solid technical knowledge is glossed over and made to be a joke, and what's left in the limelight is just a bunch of nostalgia. I actually got angry quite a few times because it was such an overtly obvious wankfest. It was like watching some stylized infomercial with a bunch of people feeding you their marketing propaganda. The entire thing feels like some elaborate ego exercise - an extension of Dave's speech at the Grammies, where he continuously pats himself on the back for making a record the 'real' way, while all of his competitors are cheaters or something to that effect.
From what I've heard Sound City didn't close because big bad digital came along and destroyed it, along with the soul and fiber of music. It closed because it was a dirty shithole that nobody bothered to clean for over 30 years.