Atlus took everything it learned from Persona 3 Reload and went all out for Persona 4 Revival, according to series producer Kazuhisa Wada.
In a move that was a little controversial at the time, Persona 3 Reload actually remade the original Persona 3 rather than the expanded Persona 3 Reload release. Some content introduced in the re-release eventually made its way into Persona 3 Reload thanks to the Episode Aegis expansion (and a few unofficial mods), but things are different this time around.
Persona 4 Revival is a remake of Persona 4 Golden, not base game Persona 4. So, why the change? We asked Atlus' Kazuhisa Wada about the different approach in a chat from Gamescom. He explains "there was a lot that we wanted to do" with Persona 3 Reload, but since it was the team's first go at such a substantial remake, "we weren't really sure how much we could handle."
Eventually, Atlus decided to simply focus on "making the base experience just the best it can possibly be." The Episode Aegis arc was a section the team thought could come "later as something when we have the time to do it, we can give it the treatment it deserves."
Things were different by the time Persona 4 Revival rolled around, Wada says. "Marie's story was so inherent to the main story of [P4 Golden] that we couldn't release it later" like the studio did with Episode Aegis.
For context, the Episode Aegis expansion serves as a sort of epilogue to the base game, making it quite simple to add after launch. But Persona 4 Golden's addition of Marie is laced throughout the entire game. "So what we decided is, 'Let's take all the lessons we learned from P3R. Let's incorporate that in. All right, it's time to roll up our sleeves and it's time to go and put all the effort into making a full remake.'"
