I'm hear tell that it does 'do' Dolby 5.1 over the HDMI ARC* input and presumably the optical out, which can carry Atmos. The streaming services in the TV apps generally use that, but who's getting what from the respective streaming services' apps on which TVs is a bit of a dog's breakfast at the moment. Delivering the Dolby 5.1/Atmos streaming is the reason according to them for not supporting eARC in 2019, which isn't much help if you want a disc player to the TV with a single connection.
With disc playback I just use dual HDMI out of the Disc player - Video HDMI 1 straight to the TV and Audio HDMI 2 to the surround system. It avoids/solves a bunch of issues, plus I run optical out from the TV for everything else that comes in through the TV. Over the HDMI ARC worked for me before, then with couple of new devices added it started being cantankerous.
Depending on how much color accuracy and general dialling-in/calibration matters to you, you might enquire with a pro calibrator. In the U.S. you can try to dig up some of their commentary on AVSForum. I imagine you've likely looked in on there with regard to the TV in the dedicated thread for the specific model, but if you haven't looking in the 'Display Calibration' subforum you might find some commentary along those lines - jrref and D-Nice are two usernames, off the top of my head, who are gurus in that field, the latter being an industry consultant. I won't allude to some of his past commentary on some Samsungs, because different model series/years come into play to some degree, plus guys like these can see things most of us wouldn't even notice.
The turd in the soup sometimes, though, is some high-end TVs with out-of-the-box white balance being some way off even in their most accurate picture mode, often largely so easily solved by a simple two point adjustment that it looks deliberate. That's a given for the vivid modes used on the showroom floor, but sometimes a headscratcher in the picture modes that are supposed to be accurate (usually with 'Cinema', 'Custom', 'Professional' etc in the name).
If you've watched the U.K. HDTVTest on YouTube
https://www.youtube.com/watch?v=0oiLCk94lS8 Vincent Teoh is another guy who really knows his stuff.
*According to an update to one review (scroll down to the 'TV channels, recording & sound' paragraph) - https://www.flatpanelshd.com/review....&id=1557215154