Sanji was caught of guard getting pinned, huh? The case can be made so was Carrot when she noticed Nami get captured by Smoothie.
Hell, lets say they were all caught of guard. Would they have been able to escape is the real question. You can say no to that, which I understand.
Lets also not act like Sanji didn't struggle with Daifuku.
Not saying Daifuku is stronger than Sanji, just that he would require more effort to beat than the average Charlotte family member. And he was in a rush to save his family.
No, they wouldn't. Because they'd have to bypass Katakuri's advanced Observation Haki. If Jinbe couldn't do a thing to him (and we know how powerful Jinbe is), what makes you think they'd have a chance?
And I don't feel its necessary for me to post the pages of Luffy getting utterly demolished by Katakuri.
Because at the time Yamato was with him. And he personally knew how strong she was, so he sent her to help protect them. Then Luffy tried to go to the top of the dome with Zoro as company before being shut down by Queen. You seriously forgetting this?
I'd rather see what she can do in her base prior to going Sulong because of how temporary it is and the negative effects of using it with your lost stamina. So I see it as a last resort unless Carrot is foolish enough to do it straight off the gate like that despite knowing how taxing it can be.
And my point was to show how meaningless it was to determine those as factors for her usefulness. Didn't she sense danger before Nami and Chopper and shielded them? Seems like she's more combat capable than they are.
Wasn't she also swift enough to catch Diesel, a living train, easily?
And Luffy couldn't rely on her to do stuff and was a burden to others?
Concerning how strong she is, well, I'll only refer to Pedro's words about her:
How good though? I guess we'll see in the next coming chapters with her potential match-up against Perospero.