Here are the issues I have with FFXV (and I put in over 150 hours into it)
1) To understand the full main story you must watch that anime short series they put out, and play all 4 DLC's. If you really want a crystal clear explanation of everything that is going on. Then you also need to watch that movie (which takes place before the story begins) and do some reading as they put out some comics/books. This is my biggest issue with the game. If you just play the main game through (before playing the episodes) you will have so many questions about whats going on.
The first time I played FFXV was summer of 2019 by this time all the DLC was finished and the unreleased ones were canceled. I first played through the main story and when I had beaten it I really didn't fully understand what was going on, nor did the ending make things clear to me. It actually wasn't until after I beat the Ardyn episode that things made sense.
While I think the story (whole package) is really good, the way it was put together was terrible. You should never have to buy DLC to explain parts of the story as you are playing through the game (episodes 1-3 take place as you are playing the main story and unless you buy those episodes you will have no idea what happened to your party)
2) Final Fantasy XV feels way to floaty, the combat is really weird and when you jump and land it feels..... soft, i don't know how to explain it. I noticed this within the first time I jumped in the game and did not like it at all. But this is a personal preference, others may like it, idk.
3) Breaking the game up into chapters. No idea why this was done, but it makes the world feel locked, I did not like this (maybe others did) as it felt restrictive.
4) The world felt.... kinda hollow, some places the design was fantastic, others was very blah. When comparing this world to past it ranks a lot lower IMO.
With those aside, the music is fantastic, I loved the relationship between the four characters. I actually think this was the strongest part of the game.