No. again, I made you a list of things that are lost if you skip it. Those things are narratively important. Everything is not about what we - as reader - learn, its also about what characters will learn as well.
Yes, we do.
Again, revelations are not only what matters in that type of chapters.
Because that speech is THE speech of the story.
This is not a simple rambling of a character. This is a speech that will transform the way we see the world and the way all the character see the world. This speech is a central composant of One Piece, that's why it is so long and why Oda makes so much emphasis toward it.
Its literally the entire world of One Piece watching Vegapunk. Its THE game changer. Its not just about us learning thing, its Oda creating enough momentum to end its story correctly.
Realistically, the main reason, being charitable to Oda, for this speech, is to explicitly deliver details to more casual readers (and secondly, the characters in-verse). When this sort of dialogue appeared pre-ts (like when the full story of Ohara was revealed), it would tie all the hints gradually revealed throughout the course of an arc together,
and add more crucial detail to give the reader a full picture.
Good writing does more showing than telling, and has a high ratio of information to dialogue. When Oda wants to be, he can be pretty good at this. Imu calling for the Mother Flame to be ready, stating that Lulusia never existed afterwards, along with the revelation that sea levels rose immediately after Lulusia's destruction and the elders calling for a "great cleansing" was showing, not telling. A high concentration of information with nothing more than the natural of dialogue of the characters within the story, giving readers just enough pieces to put the puzzle together.
Vegapunk's speech was the opposite. It was hamfisted and drawn out. Even if you disagree on the former, whatever value was provided to casual readers and to the characters in-verse to move the plot along did not require
nine chapters across
four months- honestly most of the frustration wouldn't have materialized if it were contained within a chapter or two, which it easily could've been.
Skim through Alabasta, Skypeia, Water 7/EL, it's night and day versus WCI, Wano and now Egghead with how much information is conveyed to the reader per chapter. And those arcs were anything but rushed.