Edit: Open spoilers for P3-5 in this post
Call me biased (avatar) but it really is imo. Persona 5 kinda disappointed me in some ways, and especially when it came to the protag and co. Cast in persona 5 didn't really seem like group of close friends to me, unlike Persona 4 (or even 3). I couldn't shake off that feeling while playing that P5 characters lack chemistry. Maybe one day I'll come back and change my mind but...
Friendship isn't the problem. The cast of P3 really aren't friends either - Remember that a random PC greeting you every day when you come back to the dorm is a thing in that game. Everyone in that game sorta does their own thing. The difference is that their cast is a cohesive group. They're the SEES, and they deal with the threats that appear every new moon and investigate the Tartarus in hopes of uncovering the mystery of the Dark Hour. The P5 cast... largely fucks around, and their goals are mostly shallow and predictable.
P5's concept is much more active than the past two games' which were much more passive for their unknown forces and mystery plots. They're the Phantom Thieves of Hearts here to bring justice to a world by stealing people's distorted desires. They're sharp, precise, and deliberate, and the game's presentation backs this up - breaking chains, throwing knives, stylishly sliding and swinging portraits in menus, jumping and bounding in dungeons. The story does not. They fumble around on selection of their targets, bicker over stupid shit (that stupid Ryuji/Morgana feud that sucks up a week in-game), and are nearly as often forced into picking targets by a third party as they do pick one themselves (3 of the game's 7 main scenarios feature them picking a target in part due to blackmail).
There are some issues the scenario writers seem to have identified but don't handle as well as in previous iterations. In particular, characters introduced late into the game tend to be less memorable than their earlier ones so they need to be made to stand out. P3 largely sidesteps this issue by injuring or forcing to the sideline some of the major players and introducing increasingly whacky characters the later on you go - a kid, a dog, a goddamn robot - to varying degrees of success (most people hate Ken, and rightfully so, but Koromaru is inoffensive fun, and Aigis is... just wonderfully woven in the later you go). P4 adds the extra Mitsuo dungeon in after getting Rise, largely to pad out the playtime, but I think most people are onboard with it since the cast get along so well. P4 also introduces the last PC, Naoto, in earlier cutscenes to ease her into the team later and makes her tremendously useful to help along the investigation and have her stand out more. In P5, Haru just... appears. She's just there and your team handles her problem in particular because why the hell not. This is a really common complaint already though and I don't think much else needs to be said than put it next to the other games.
Anyway, what I'm getting to here is that the writers in P5 seem to have identified to some degree that newer characters need to stand out more. Each new addition to the team is... generally more useful than the last. Yusuke's a character alright but marginally smarter than Ryuji and Ann. Makoto's actually smart, and Futaba is implausibly technically proficient. Haru's existence kinda throws a wrench into the model but I think she's more an outlier - the design team wanted another dungeon in the 2nd act, and the writers just threw up their hands and said 'fuck it' - Her presentation in-game is pretty consistent with that imo.
There's the localization too. It's spotty, maybe understandably so when I consider the monster script size to this game (and props to Atlus for actually going back in Royal and rewriting and even rerecording some lines), but that doesn't change that it's spotty. The shit intro with Sojiro was enough to turn me off of vanilla P5. Like, stinker lines like "You were expelled once before. To think you'd apply somewhere else" are just fucking awful and do nothing for me an English speaker, except maybe imply Sojiro is insane which is clearly not what the scene's framing is going for.
