This is what makes the anime unwatchable for me (at least compared to mdoern seasonal animes).
You get one good episode and then a bunch of fillers/poorly animated/poorly paced episodes again.
Imagine what the OP anime could've been if it really started just recently and was made like Demon Slayer or AoT (seasonal anime by a great studio with perfect pacing and animation for every episode).
The underlying manga content of OP has massive dips in quality for weeks at a time and pacing issues since the TS. This is a scaling issue because the arc wraps up with Luffy and so he gets stalled, in short arcs that is fine, in 200 chapter long arcs it becomes ridiculous.
(I'm not shitting on OP, the peaks are still amazing and even a
relatively "bad" chapter generally has 2 or 3 great pages).
How could they have made
a great adaptation of Luffy running around aimlessly for many many months on end as he did in the manga?
Emphasizing the goated chapters with goated episodes is the best they can really do without cutting large amounts of content from the manga (that the editors should have helped Oda with in the Manga) or blowing a shitload of money animating runpiece setup chapters.