Hyogoro is one big metaphor for Wano. If Wano were a human, then he would be it.
Once before, he and the land stood strong, bountiful and proud.
They would later be seized by Kaido and his pirates. Hyogoro as a prisoner, and Wano as Kaido's base of operations/territory.
They are shells of their former selves due to the abusive treatment by those who conquered them via deceit and manipulation.
It was intentional for Luffy to encourage Hyogoro, as it's essentially Luffy inspiring Wano itself to rise up from its predicament. To restore what has been lost, and birth something new. Likewise, Hyogoro teaches Luffy his techniques; Wano joining its hands with Luffy, who can't beat the enemies controlling it alone.
Now in this chapter, Hyogoro has been infected by the Ice-Oni, which allowed him to return to his prime for a bit. A sign that Wano itself has a fighting chance. However, he will become a mindless monster that will strike anyone down indiscriminately if they can't cure him. Kaido plans to drop Onigashima onto the Flower Capital, turning the country into a lawless land of violence, unless the Alliance prevents it. There's a ticking time bomb factor in both scenarios.
Hyogoro lays it on thick on the meaning of this battle.
We've had several emphasis on the coming dawn, through Toki's prophecy, Yamato's hopes in Momo, Pedro sacrificing himself, and the fact that the battle is being waged during the night. The hour of the tiger occurs around sunrise. The tiger being the dragon's natural foe in Eastern mythology. The current enemy is a dragon, and his defeat timing perfectly with the emerging light is the kind of subtext-to-text practice Oda likes to employ. Remember Sky Island? Cricket wanted to prove the existence of the City of Gold. How did Luffy do it? By ringing the bell that was referred to as the "Light of Shandora," the light of the Golden City, proving its existence in the most literal fashion.
The next time the sun shines over Wano is when it is free, just as Hyogoro will be.
As for the rest of the chapter, I'm glad Perospero can get on to more interesting things once more. He's the wildcard on the island, as he isn't fond of either the Alliance or Beast Pirates. Whatever action he takes can tip the scales in one sides' favor.
Chopper has a lot of importance levied on him this chapter. Everyone on the Alliance side, including some of the enemies, are counting on him to prepare the antidote for Queen's plague. This is his biggest test as a doctor. Even someone like Marco, an expert doctor, has placed his hopes on Chopper. Succeeding here would go a long way for him accomplishing his dream.
Speaking of importance, Sanji's indecision on helping Momo or the Scabbards, I think will lead to a third option that kills two birds with one stone. We've been waiting to see him pull off his grand clutch moments, and this might be time But, if he did come down to one of the available choices, helping Momo is more likely. Sanji doesn't know who Yamato is and might be concerned for Momo. Kin'emon would want Sanji to protect Momo before him, and Sanji and Kin have a good relationship, after all.
We're reminded of the island floating. This is actually the first time we are since 999, if I remember. It's good because the tension was starting to lasp a bit after the last few chapters. This chapter did a great job re-establishing the severity of the situation. Marco can't hold off King and Queen forever (Perospero arriving to possibly cause more trouble for him), the Ice Oni are starting to take its toll on the Samurai, and Onigashima is still approaching the Capital.