P3P has its fans, a lot of people love it, so you might as well, I don't know. Rather than telling you what my thoughts are, I'll just share the differences between FES and Portable, and you can decide for yourself whether or not you'd be able to put up with the cutbacks in Portable.
FES:
- No party control
- 30 hours of extra content added via a new epilogue episode "The Answer"
- Full 3D overworld exploration
- Extra music tracks associated with the areas that are cut in Portable (either because no exploration, or because no The Answer)
- Full cutscenes (in-engine and FMV)
- Fewer difficulty settings
- Retains the Fatigue system
- Missing QoL that P4 added (and P3P retained)
Portable:
- Full party control
- New female protagonist route, including all new social links
- No 3D overworld (exploration segments are point and click VN style)
- No "The Answer" content at all
- No FMV cutscenes, and very few in-engine ones
- Fatigue system is gone
- Expanded difficulty settings and options
- Retains QoL from P4
As you can see, it's not clear cut. The FeMC route in Portable has a lot of fans (and FeMC is great, so this makes sense), and we got a lot of great UI and QoL and mechanical upgrades (in combat, dungeons, and social links alike). There is definitely a lot to like about Portable.
However, here is my problem - P3 was never a particularly well playing game, and while Portable sands over a lot of the rough edges, it doesn't... rebalance the game. P3 was never designed around full party control or the lack of a Fatigue system, and those changes in Portable gut the game's difficulty thoroughly and make it a cakewalk starting about halfway in. Additionally, P3's
biggest strengths, IMO, were its amazing atmosphere, story, and storytelling - by getting rid of the 3D world, cutscenes, and accompanying music, almost all of that is lost.
For context, look at this intro cutscene in P3 FES:
You don't have to view all of it, but I think it gives you a good idea of the kind of mood the game establishes.
This is the same scene in Portable:
You only have to watch the first 2-3 minutes.
To me, the loss of the things P3 does well is too great in Portable, without the weaknesses that the game has (that Portable is supposed to account for) being addressed adequately, so the whole thing ends up just being a far worse, far weaker game. YMMV of course, particularly if P3 clicks for you for different reasons than it did me. But that's the big issue with P3 for me.
Lastly, to your point about P3P reviews - I believe the Metascore is tied with the score for the FES version, and a lot of P3P's reviews were in context of such a beloved and recent full fledged console game getting such a great portable release just a couple years after its initial launch. Which is not to say the review scores are unearned, but it is important to keep the broader context in mind when looking at these too.