Blablabla.
You're on copium.
BB isn't the final villain, the World Government is.
Roger "In 20 yrs someone will surpass us"
Beating Rocks 2.0 isn't gonna make Luffy surpass Roger, beating the WG, that Roger couldn't challenge because he was too early and did not have access to Poseidon, will.
The WG is the final villain, you're just on full on copium because it's IMPOSSIBLE to write an arc that will feature an even greater alliance than the current one, with stronger protagonists, and have none of the villains be stronger than Crydo and Big Meme
You don't understand basic narrative structure. Kaido and BM were doomed as soon as it was made evident they were gonna fall before endgame.
They're not ending this story as top 10 strongest.