That's the point. This is an arc where the Strawhats beat opponents seemingly out of the stratosphere for themselves. Kaido one-shot Luffy, now he's going to get beaten by him.
Also, Page One was not "clashing evenly" with RS Sanji. Far from it. As funny as it was that Sanji said he'd take him out for good and didn't, there's a clear difference in how Page One was taking hits from Sanji, to how Sanji was taking hits from Pay Pay
Alabasta has been the only arc in One Piece where everyone got a fight. Yes, someone will have to miss out, but it makes more sense that it's only one Strawhat that misses out, as opposed to six of them. Or maybe, maybe Oda matches some of the WCI group against BM Pirates, but I'm still wary of the role their playing.
I'd say it would be stupider for Luffy's crew to play a negligible role in defeating the first Yonko. The Scabbards can beat a few Numbers then get hypetooled by Kaido and the Calamities. Leave the actual fight for the Strawhats.
Also, I find it very hard to think that, in the case of Ashura and Denjiro in particular, that Oda is setting them up to have a focused 1 vs 1 fight. And I say that because, with what's shown so far, the two do not have a unique fighting style. They are (along with Kiku) bog standard swordsmen, with nothing unique about their fighting style. Kawamatsu might be getting set up for something since Oda's actually gave him a distinct moveset, we'll at least see the Minks Su Long.
And that's the thing that is always in the Strawhats favour- they have a unique fighting style. A fight between Franky and Sasaki, or Brook and Who's Who, is always going to be more interesting than anything a plain fighter like Ashura or Denjiro can come up with.