For me Oda try to save the Calamity as long as he can.
He making them alongside with Kaido the last step of the war, who begin inoffical with Luffy attacking the beast pirates.
As step for step, Luffy first take out a normal beast pirates>then take out gifters>then face multiple headliners(Apo at the lead)>Numbers join the battlefield>probably soon two flying six(Ulti and Pageone) joining the battlefield too.
You can see that Oda goes step from step and even making every new step harder and harder, Ulti alone of course shouldn´t be the big problem for Luffy. But the point is and that is important, the numbers of the beast pirates are to much and with every new step far stronger enemies shows up, that was literally also the point of Zoro:
Not only the numbers, but they have in combo a overall good and strong crew, at each new step a stronger beast pirate shows up(Even though Apoo is a special one who should be at least at flying six lvl too) which make it harder for Luffy and Zoro to deal with it.
In normal states Luffy shouldn´t get much problems, but the numbers and strong pirates, in combo with very strong characters as Ulti and Pageone, I wouldn´t be surprise if Luffy don´t showing the things in next chapter which we expect, which means I can even see a "hype" chapter for Ulti+Pageone overall.
Luffy and Zoro didn´t yet reach the calamity or Kaido himself, but seeing Zoro states in the panel above and also Luffy in current chapter, it little show that the raid don´t gonna be easy...
If Luffy and Zoro already getting in kinda these states(injuries) and having problems, it literally hard to believe how the other strawhats and other alliance member gonna deal with that. We speaking about 4Supernova(+Kid crew) and they already having big trouble, in adding that they "only" face until now Apoo+1Number and Headliners.
And after Ulti and Pageone, the next and last previous step gonna show up before Kaido making his move, one Calamity and I want to see how Luffy going though these walls.
For sure the war will be very exicting and I want to see how the Alliance deal with such a strong force. It make sense for me why Oda try to hold back the Big mom pirates, the alliance can´t get the problem to deal with a another Yonkou crew, that is for sure...