Your flaw is you assume most of warfare has occurred between organized states. Like Germany and France.
This is false. Most of warfare has been tribal warfare: raids, subjugation and expulsion. Not to mention every peasant rebellion in history, most of civil wars and slave rebellions. The aristocracy simply did not negotiate with peasants. Colonization of Africa is another good example. Excluding states in North Africa Europeans simply planted their flag and did whatever they wanted.
Now, that is true it is the first peace treaty. So when comes the second known peace treaty? Or Third! As you can see they are incredible rare, not to even mention Bronze Age collapse and all the history before 1274 BCE... You cannot generalise exception. Back then human societies were much less organized and they simply didnt bother to make a peace treaty because states were so weak. Another good examples are Ancient Egypt long-term enemies of Libya and Nubia. Egyptians didnt send envoys to negotiate, they send an army and massacred them and came back. No need to negotiate when you kill enough.
You're moving the goal posts. I reacted to this statement: "(spoiler: most of history there were no negotiations, it was either a raid, capitulation or annihilation)." NOT to: most warfare in history was not between states.
But even with goalposts moved, you're still wrong. Anthopologists who have actually studied tribal wars have found that most of them have recognized rules of conduct and many more end with negotiated settlements than with conquest or eradication. In the absence of state control, tribes regulate their conflicts through raids and blood feuds, yes, but they also have institutions like blood money, ceasefires and peace agreements.
Your generalizations about social conflict and colonialism are equally baseless. There are many instances of aristocrats negotiating with peasants. More so with urban than rural leaders but they did need the labor to generate the income to afford their lifestyle. If they thought talking directly to a peasant was beneath them, they could send their non-aristocratic sergeants or use the church as an intermediary. Regarding colonialism, Europeans usually secured treaties with native rulers, in part because their European rivals had some regard for such contracts. Of course, it was also less costly to defend far away colonies if at least some local rulers recognized your claim, and perhaps even joined you in a fight against other local rulers.
Finally, next time please do a simple google search for "Egypt Nubia diplomacy" before claiming there was none.