What do you mean by "this is the first real new RPG" ? What does this game have that any developer would want to 'top' ?
The defining RPG for this 'era' is most likely Witcher 3. It has had massive success both critically and commercially, and served as the inspiration for future RPGs that came after it (Final Fantasy XV).
You could also make the argument that Persona 5 is another defining RPG of this era. It's effectively considered one of the greatest JRPGs of all time, and has the best critical reception that the industry has seen since the release of Final Fantasy IX back in 2000.
FFXV is an afterthought when you compare it to the other, better RPGs of this era.