I wouldn't put much stock in that review. If the Port has the features you want I bet it will sound fine, especially if you use the digital output to an external DAC. I didn't realize Sonos eliminated the optical output though; the Port just has coax digital out. Maybe someone on here has the Port and can comment.
@Sophoheilip did a teardown report, so maybe can offer some thoughts?
Also, you can probably still find the Sonos Connect Gen 2 that works with Sonos S2, but this won't have airplay.