If Noctis and co were actually doing something substantial while these other major plot points were going on, then yeah this would have totally worked.
Instead it's "full scale war in a massive city vs. pushing a car".
Ideally they would see a unique perspective on a massive story, but in FFXV it's more like Noct is a clear cut non-participant in the story.
Say what you will about ME3's ending, but the overall story arc of ME3 tackled this EXACT concept quite well. "Earth is invaded, Shepherd leaves Earth and travels the galaxy to the front lines of many battles to forge alliances(all massive missions with big stakes), and then returning home with the support for the final battle."
The key difference was the middle portion of the game. Shepherd wasn't on his home turf either, but he was fighting the war in his own way on the outside. Noct was just blindly following Ardyn, without any agency at all.