He has some damn respect for the Yonko, thats why they are his goal. He is "reaching for the Stars". Remember what his words were when he entered New world? Only the strong survives, weaklings die or should stay in paradise. And the first ones he meet in new world, are weaklings compared to him.
So what shall he do next? His goal is the ultimative goal, for that, he needs to be as strong as possible, whcih means he needs to get as much experience as possible, so he needs to fight stronger ones. And this is what he does. Straight up for the motivation: "Get stronger or die", like he said at beginn of new world. And see what, he is still alive, still getting up, even going into 3 Yonko territories and confirmed at least one straight up fight against an Yonko, which back then acknowledged him as CoC User and now acknowledge him as "little Monster".
He doesnt go blindly or disrespectful into something, but he has to go into to figure out how to deal with it. He cant go the easy silly Luffy way. He goes in with all or nothing, grow or die. Thats it and since now, he didnt die, he went stronger, each time.