I'm sure the Wano/Rocks connection will be addressed from Rocks' perspective in the future. We needed the story from Kaido's perspective. I mean look at what Kuma's flashback has done for his character. Kaido's 9 page flashback was way off the mark of what could've been the best villain in the series so far.
Also, Mom's arc with her family was moved from WCI to Wano to never get resolved. Which is why this is my dream.
I used to think it's cope, but I'm starting to lean towards their comeback. Pudding kidnapping/Kaido's mini flashback makes you think there has to be more.