I saw it in the cinema, and while nothing looks "off," I'm pretty sure grain was removed - it doesn't have the grain structure of a film shot in the late-70s.
A few years ago, I bought the most basic Panasonic player to watch 4K discs on my plasma. It did a very good job of converting HDR to SDR with the default settings, but it also provides some user settings to tweak the image to your liking. When comparing 4K discs directly to their blu-ray...