While it's practically confirmed that both Kaido and BM will fall in Wano, it doesn't necessarily mean Elbaf would be unimportant/neglected to a cover story. in fact, Elbaf is significantly important to the plot, it would be the key and the unbreakable sword for pirate king Luffy to destroy the world government.
As explained by the
Ragnarok theory written by Admiral Ryokugyu before, One Piece has many Norse themes (Oda's first inspiration was a viking cartoon). Ym-sama could even based upon Norse god Ymir, while the world nobles who are hailed as the "gods who created this world" are based on Norse gods. and the giants are the ones who destroyed them in norse mythology during Ragnarok, final war. furthermore, it's heavily implied the giant hat in Pangea Castle belongs to Joy Boy, the owner of the One Piece treasure, which possibly confirms that he's a giant too.
Just ask yourself, why would Oda introduce Elbaf as the most powerful country in the entire world and save it up untill the massive war end of story ? when Strawhats reach Laugh Tale, they would already know all history and how Joy Boy failed to take down Imu and the original 20 world nobles. overwhelmed by the world government's strength, they will seek help from the strongest military force, the possible home and race of Joy Boy, Elbaf, to face the massive power of the WG.
It wouldn't only be ironic and
laughable to see the world government get destroyed by the same race of Joy Boy 800 years later, but Elbaf and its giants also have been tricked and humiliated by the world government multiple times, they manipulated Omiio and Kashi to work for them, worked with the underworld broker Mother Carmel to take John Giant, strengthened Mother Carmel which resulted to her raising potentially powerful agents in the future, allowing the village of Elbaf to get destroyed. It would be remarkable to see that end of story, instead of helping the wrong side (Big Mom) they will help the good side (Luffy) in becoming/after becoming the pirate king.
Luffy is definitely strong. he has the strongest types of Haki, immense physical strength and unbreakable will. but there's an even bigger power that lies within him which he doesn't even realize. and it's just as Mihawk said:
his extraordinary gift to recruit allies and friends. so what's better than getting the strongest country as your ally against the strongest obstacle.