Yeah I expected the first arc post Wano to prove why Luffy is finally worthy of being a Yonko now, especially to the world itself and the World Government/Marines most of all but even other contenders and remaining Yonko.
This is where he will finally be able to truly prove himself for Shanks and meet him as his equal now too truly.
I just wish Luffys bounty was higher given what happened with his fruit too but Oda seems to have done this matching bounty thing with him, Law and Kidd to prove, whereas all 3 might have gotten the same bounty, ONLY Luffy was deemed worthy of being a Yonko as you said ofc.
Kidd and Law dont have the territories and influence for Yonkos. They dont have allies nor crewmates strong enough to be considered a Yonko crew, not even remotely. Kidd has 30-ish people in his crew but he went for quantity/size over quality ofc. Shanks has been said to have the most balanced crew and Beckmann being close to his level, like Rayleigh and Roger.
I really wanted to see Law and Kidd get mega wank post Wano and become Yonkos themselves, but theres no way in Hell that Oda was gonna sacrifice Blackbeard, Luffys ultimate nemesis/foil for decades and Shanks (self explanatory especially with Luffy ofc) for those two. As much as I hate to admit and accept it, Kidd and Law were last minute request additions for Oda to include in the story ofc, he was told to design and create them a day before they were needed to be added in the story. Oda even said himself, he expected Kidd to get a MUCH greater role/importance in the story but ironically it was Law instead ofc, much to his surprise too.
Kidd is meant to have haki including CoC but Oda seems to have purposely abandoned that and he only gave Law haki as to help him break out of "Doc Q's free, instant gender reassignment therapy" as far as I remember. I dont recall Law using haki before that?