I reached the same conclusion researching an upgrade for my dad's stereo system.
The Mac Mini (or something like it) + DAC/preamp/headphone amp (possibly all separate) seems like the best compromise to future-proof the system.
Traditional hi-fi manufacturers' solutions (e.g., Naim Uniti) all seem to be expensive, clunky, and quickly obsoleted by the rapid advance of digital audio technologies. Running a full computer and operating system (+ storage management) seems like overkill for an audio system, but the crippled alternatives in the hi-fi boxes are worse for functionality and expansion options.
You also have a lot more choices in software – running a full-fledged computer allows you to switch between a hi-fi/high-res audio library or casual streaming like Spotify, Tidal, or Qobuz.
I gave up on trying to figure out high-res formats and took the easy route – ripping my CDs to ALAC as a way of increasing convenience and backing up the discs. No monthly fees, no hassle.