It's cancelled.
To release and support The Last of Us Online we’d have to put all our studio resources behind supporting post launch content for years to come, severely impacting development on future single-player games. So, we had two paths in front of us: become a solely live service games studio or continue to focus on single-player narrative games that have defined Naughty Dog’s heritage.
Those are not your only two options. Multiplayer games are not inherently live services. Some of my favorites are from a console generation where patches were impossible and the mode was thrown together in a few weeks of dev time reusing assets from the campaign. The winner of "best multiplayer" just days ago was not a live service game.