"On the right track" is probably the best way to describe FFXV. We're not quite where the series used to be, but it's a step in the right direction, and I think it will get better from here.
The 'series' never went anywhere. FF has always been about experimentation and even if you didn't like XIII, plenty of people did. I think people's (especially Westerners) tastes have changed drastically in the past decade with the influx of the Skyrims and Witchers into the RPG norms, meaning what always worked for FF became somewhat outdated. FF XIII tried to reconcile the two but its focus on a storyline too similar in style to past entries (being too 'anime') and linearity did not gel anymore. XV has successfully adopted the open world model but I do hope it does not become the norm. Something like FFVIII's 'open world' can work as well.
However, I agree that it did stumble with XIV 1.0 but, as we know, it recovered fantastically (pun intended).
BTW Aside from FF: ATB, the mobile FFs have been excellent as well.