The different in every scene is that in most these battles with you call out the Strawhats had energy and the spirit to fight back. This time Nami already lying down well crying, Usopp get beat up badly again. They where done, at that is the different.
Zoro stand on his own when he defeat Mr.1
Luffy and Zoro where okay without any much damage taking by the Cp9, they didn't cry because beeing weak as Nami right now did.
Chopper and Usopp fight back on their own in a equal battle before they take the advanced in the end.
In the most battles the fight where equal and the Strawhats overcome their own limit with their spirit.
Ulti and Pagone vs Nami and Usopp are totally different, they complete stomp them in few seconds while Nami even crying out and was about the get killed. They don't even scratch the dinos and we speak about guys who tank G3 attacks, how Usopp and Nami gonna knock out guys who have G3+ durability and insane stamina? Not like the previous guys with getting one shotet, Ulti and Pageone can tank many much and don't gonna down by simple attacks.
Oda know this and do something with he didn't do for battles like Zoro vs Mr.1, Usopp and Chopper in alabasta and the other battles, he save Nami and Usopp right now with OTama.
If Otama wasn't their,Nami would simple killed off, probably they escape in the next chapter and the battle ends here for first.
Without help of strong opponents Nami and Usopp can't take Ulti and Pageone, it was simple shown by Oda now.