The article suggests that it is probably not: "It may also be possible to implement S/PDIF on a sufficiently fast single-core microcontroller. Unfortunately, a

The article suggests that it is probably not: "It may also be possible to implement S/PDIF on a sufficiently fast single-core microcontroller. Unfortunately, an 8-bit µC like the AVR used in the popular Arduino board probably wouldn’t be fast enough." Perhaps because even if it is fast enough for S/PDIF encoding, you'd want to do other things with it, e.g. synthesizing.