Hopefully Souma will tell them that honor and pride have no place in a war for survival.

No. What he sees are eagles that have clipped their own wings, because they are being bound by cultural forms such as “Honor,” and “Fair Fights.” Night attacks. Poison. Barriers. Boulders to destroy those make shift fortifications. Fire attacks. Cutting off supply routes. Any number of tactics… all left to the side because these guys want to charge headlong into combat and get shot full of arrows.

And this is the tactic the Zoans have been using for decades. Is it any wonder the humans think they are just semi-intelligent beasts when they don’t learn from their mistakes?

When he wrote the book doesn’t matter whether or not wars settled down. This very similar to how generals of world war 2 wrote about their experience and military treatise after the war. Sun Tzu is said to be a general and tactician. His work have been peered reviewed for centuries by generals and tacticians. They would have noticed flaws of that work by now and they would never have adopted some of it and modified it to be used in modern setting if they think it is flawed.

It is also used by business and thus applicable even during peacetimes.

As I see it , what he see is a bunch of eagles defeated by a bunch of doves.

no even if you say that since they’re persecuted they spend all their time trying to survive rather than being cultural, sun tzu was able to write his book because the time was a time where wars had settled down wasn’t it? nothing thats still fighting for survival can try to expand their culture until their safety and food supply has been confirmed and is enough for people to do more than the essentials, however since the tribe just lost their village and many people they deffinetly do not have enough people for that and even before they were most likely living very much on the border of that state

He could counter that precisely because he is human he understand. Afterall, the Art of War of Sun Tzu did say

“If you know the enemy and know yourself, you need not fear the result of a hundred battles. If you know yourself but not the enemy, for every victory gained you will also suffer a defeat. If you know neither the enemy nor yourself, you will succumb in every battle.”

Zoan don’t know their capacity thus they don’t know themselves and they don’t know humans so they defeated everytime.

If he teach them their capabilities then they would know themselves and since he is human they would know the enemies.

In his eyes it is like seeing eagles losing to a bunch of doves.