Not really. Persona 5 was originally on the PS3 and was at one point delayed because they started making a PS4 version. It released in Japan on September 15, 2016, while the worldwide release was on April 4th, 2017. I believe that's enough time to warrant a "Definitive Version" release at this point, more so with the type of DLC that was available. If they do add a significant amount of new content (like P3 FES, P3P, and P4G), it would be perfect.
Another game in a similar situation (as far as release dates are concerned) is Nier: Automata, which is getting a definitive version with bonus content released next year.
As mentioned earlier in the thread, the same thing happened with the Crash Team Racing: Nitro Fueled announcement. The original trailer only had the PS4 logo, yet it's a multi-platform game. While it's true that Final Fantasy 7 wasn't on any Nintendo systems during the time both Smash 4 and its DLC were released, Cloud Strife (and co.) had already made an appearance in a couple of Nintendo games:
- Kingdom Hearts: Chain of Memories (NPC)
- Theatrhythm Final Fantasy (Playable character)
- Theatrhythm Final Fantasy: Curtain Call (Playable character)
- Final Fantasy Explorers (Transformation)
The same goes for Joker (and his friends) who only has a single appearance on a Nintendo system at this time:
- Persona Q2: New Cinema Labyrinth (Protagonist)