I’ve played a few war games at conventions which were built around scenarios where the outcome was known. One was the fall of Gondolin, a battle at the end of the First Age of Tolkien’s Middle-Earth and the other was the Battle of Thermopylae. There was no way for the player playing the elves of Gondolin or the Greeks in Thermopylae to “win” the battle. All you could hope for was to make the win expensive for the enemy.
These seemed like they might be interesting but after a few turns it became clear there were no interesting decisions to be made. The only decision was whether or not to play the game. After that it was simply rolling dice to see how many of your forces were taken off the board that turn.
The games successfully simulated what happens when a small force stands and fights when massively outnumbered. The small force gets wiped out. Just because the simulation was correct, didn’t make it fun.