Exactly this. People have this inability to appreciate anything else besides powerscaling. And Sanji fans are biggest culprits in this regard.
For Luffy and Zoro who are basically combatants of the crew and not much else, combat skill would be most appreciated. But for Sanji, Oda has always highlighted his street-smarts and stealth and cooking. But Sanji fans botched it by tying him to powerscaling only.
Of course Sanji isn't weak. But he is not as strong as Luffy and Zoro. He makes up for the gap with his wit and other skills.
Shonen is always about combat. If Oda had any ability to write subtlety and give depth to the characters, then people wouldn't have expected different. Every arc has ended in brute forcing the oppression. Even in Sanji's shining moment at WCI, he baked a cake that did nothing but revive BM.
Fighting ability is the number one aspect of every character that's introduced. When the F6 appeared, people already had theories on their strength. In the end, they would be right to focus on power scaling because like every other antagonist, Kaido will not be defeated through peaceful negotiation. He will be beaten up and thrown out by sheer force.