Also not sure why they introduced the MacBook Pro. I don’t see paying $200 more for a touchbar and nothing else? Not sure what is “Pro” compared to the new Air.
The Mac-Mini is also limited to 16GB RAM also. That is a huge monkey in the wrench for me. If you are in need or want of higher RAM they are still selling Intel based Mac-Minis with up to 64GB RAM. I think the highlight for me was the MacBook Air, which hasn't interested me in a while.
That should work fine for the RA Opus 21. I have tried the free version of Volumio and it works pretty well. I assume you are not going to use Roon because then I would suggest Roopieee with a USB to SPDIF converter.
I do feel like I need to take a shower after going to that site and reading that article