Not talking about playback. Good network = good playback. No discussion about that.
Adding new files is a good example. Apart from analysis, watching file system changes is a pain using a NAS with seperate Core. With local files it is instant.
I nurse a handful of Cores on all kinds of different systems, some of them playing music from a NAS share. The UX of the two Cores with local files is simply better.
Here’s @danny about the subject:
Note: this may or may not be important in different use cases. And as said: no issues with playback and/or SQ.