First off, you're insisting in "Zoro wouldn't wouldn't cry outside of a 16 yo room", like this was a huge ass problem itself, and not a consequence of Zoro (in this case, Sanji) feeling like there was no way out after he had done so much. Or your sorry ass thinks he would fold Big Mom and everyone, then carry Luffy's ass out of WCI and even replace Nami's role as the navigator if necessary, right? Woro can do anything without help, thats why we had Jimbe carrying him in Egghead and Sanji needing to look down on him for him to do something to Lucci and so on
Come on dude make some effort and be realistic, context matters

When Luffy proposed to go to the Navy HQ to rescue Vivi, Zoro disagreed with it because he knows the implications it has. It's not mere fear, its not being too inconsequent when things affect more than your own. Which again falls back to Zoro not even having anyone to care about that much like Sanji had in WCI specifically
And Zoro didn't even needed to be put under such heavy pressure like Sanji was in WCI to have Luffy asking if he is a chicken for not wanting the smoke with the Navy HQ lol.
You don't even realize Zoro didn't want Luffy to go rescue Sanji, just like Sanji didn’t want Luffy to go rescue him as well. Zoro and Sanji would literally agree in almost every single decision if they were put under the same circumstances because they value similar standards for the crew's safety
Sanji himself, among other reasons, said he didn’t deserve to go back to the crew after beating Luffy, something him and Zoro agreed about in Water 7, and guess what? Luffy just punched his face, this was Luffy saying "fuck these rules, i need you with me"
In this specific moment can you picture what Zoro would do here? Would you enjoy the outcome or would Zoro end up like a clown speaking alone and getting ignored just like Nami was during "Luffy vs Sanji"? Would him show feelings and cry like Sanji "oUtsiDe oF a 16 yO rOoM?" Would he leave the crew because you think he is so manly and edgy that he would refuse to use his brain more than the usual and let Sanji and Luffy solve their things by their own? Zoro is so manly that he can't cry for legitimate reasons even while nobody is watching? Did you forgot he cried after getting clapped by Mihawk in front of Sanji, Luffy and many other people?

There are many better questions to be made here but i don't expect u guys to think about it, as i said initially, Zoro is a character than you don't need to think about that much these days, and sometimes you guys definitely act accordingly to it.
