It's not a binary choice. Arch Duke Charles could have pounced on the isolated French forces, inflicted a short sharp victory to remind Napoloen , Austria was not beaten yet, and sought better terms than those currently on offer..After Wagram what would be the point to keep fighting ,
Austria was alone and other German states were howering like vultures , happy to pick her carcass
further fighting would have utterly destroyed the Army , an important state asset , for absolutely no purpose
One fight to win or to negotiate better terms , what were the chance of that ?