I think the point is -
There WERE cavalry charges in Napoleonic battles and these had an important impact in many of those battles.
Cavalry DID charge infantry squares no matter how stupid it seems to us now - they still did it, remember infantry formed square to repulse an expected attack not just to stop any attack at all ever happening..
So these should happen in the game,
“ Cavalry is useful before, during, and after the battle.”
- Napoleon