I went with a MacMini + MacOS + Safari back in the day since it was one of the few configurations that Netflix supported at its max stream resolution (1080p initially and then 4K when Netflix released that option).

When using Netflix, hit Shift + Control + Option/Alt + D in windowed mode and you'll see an overlay with the stream information. My system mentioned above is currently playing a 4K Netflix stream (3840x2160).

Sadly the audio is still 2.0 as you mentioned.

The other obvious issue is how much compression is used on the stream. For films I really care about, I'll buy the 4K UHD BD, rip it, keep the physical media as a backup, and enjoy a less compressed stream with better audio.