It has the same problem that has handicapped OP for a while now: Lack of any tension.
Let's take Kimetsu No Yaiba for example (only because I recently finished the entire manga).
Say what you want about it's story (imo it's good for a shonen, but not great) - I was on the edge of my seat during almost every single fight, just because you knew anyone could die (except for maybe Tanjiro, but that's the obvious plot armor every shonen protagonist has).
In fact a shitton of beloved and important side characters kicked the bucket. Most of them in a brutal way.
None of those deaths was just for the sake of it though, they all added to the tension and built up the great finale.
It made Muzan look so much more threatening and menacing.
Now we go back to OP: Not a single fucking fan felt any kind of threat entering this war and this tells you everything. It's the culmination of some really poor writing decisions by Oda, especially his incapability of writing actual consequences for our prominent "good guys".
That's what really drags this arc down so much, it's unbelievable (technically most of it is nicely written for a shonen, make no mistake, that one flaw is such a huge stain though).
Imagine this raid, if this was a more brutal, modern shonen like KnY. We would be on the edge of our seats, wondering who will survive.
Instead this supposed "war" is just so fecking boring that the only topics are some SJWs not accepting that Yamato is a girl and the usual Sanji vs Zoro kindergarden.