Is it possible to play FFXIV if you don't use Discord?

[Pepsi_Plunge]

I've never been in a PF that's required it so far, even for Savage.

As long as there is a common PF-strategy and everyone is on the same page and knows what to do, usually a macro and some lines in chat are enough, sure. But voice still helps for callouts or if you need to make on-the-fly adjustment (like coordinating support in BA or repositioning if someone dies and someone else needs to take an orb or bait something instead or whatever)

A voice-party will probably recover from a mistake easier than a non-voice-party.