It's not the issue of content, it's the issue of irrelevant content. You gotta make the distinction
The Shitjao deal (even his fight against Lao G was beyond shitty) could've been handled better and shorter, the introduction of Cool Yeti Brothers was unecessary too for example, Oda trying to make to give some semblance of " depth " to Hodi was unecessary (while completely ignoring the Fishman Karate dojo for example)
People will say, it's just panels, but when you add up all those panels you'll end up with lots of pages... People criticize Kubo for his pace/panels, and I criticize Oda for sometimes putting too much useless crap in panels
It may be rude, but I couldn't care less about some things that Oda introduced and some characters too
Getting allies is irrelevant?
Because no matter how much you hate
Chinjao, his Happo Navy ended up helping the SHs in Dressrosa, and who knows they might also help him in the future, when the last war start, and even before that. The reason why he was shown, as well as the whole story about him and Garp is because Oda wanted to illustrate how the old generation is retiring and basically failing at whatever they're supposed to be doing, while the younger generation, Sai in this case is stepping up to take their place. That's why Chinjao was one shotted by Lao G, who later got one shotted by Sai himself. It all started with WB, Sengoku, Garp, all those long timers, who are either dead or have retired.
The other reason why Sai and Baby 5 got such attention is because I think there's a good chance the SHs might visit Flower country. And even for the sake of the universe expanding, all those NW nations had to be introduced at some point.I am sure it will come to play in the future, especially if Uholishia shows up...It might not be obvious to everyone now, but that's how Oda has been telling his story. I mean just look at Hachi, and the Fishmen and how they came up to play again in Sabaody and later on FI. All those characters who got introduced have a good chance of appearing again.
This is why I hate how some people who use the word "filler " in the manga. There is no such thing as filler in the manga, the anime yes. We can't be sure if those elements won't come to play. Because while we might see some developments as unnecessary, Oda later uses it, and frankly it would be better to have these characters now, than let's say when the war start. One of the reasons why the war at Marineford was hard to follow, is because of all these characters getting introduced, when the main concern is the war itself.
If we're supposed to feel involved in those characters then they would logically need a good amount of panel time, and when you possibly add to that a war setting it clearly becomes harder to be invested in all those characters, because there simply isn't enough time to flesh them out. If we take the example of Dressrosa, some characters got really redeemed, like Hajrudin who wasn't exactly everyone's favorite when he first appeared, because he crushed Ucy. I can say the same about Cabbage, Barto, and even Senor Pink who can be seen as an antagonist. So it's really a matter of wanting to develop those characters who have a good chance of appearing later on, and it wouldn't be the first time Oda does that. But I get that some of us simply dislike certain characters and just don't want to see their faces, period.
