What i think you fail to understand about reinforcements is that they forced the zerg mentality. In reality most people really prefer to win and to fight. However when a game mechanic makes doing so impossible and or futile they give up.
Without reinforcements even the worst turtle can potentially be turned into a win. And that’s what happened in 1.12 AV.
It ends up being a player decision one way or the other. Instead of the map trying to force things one way or the other which is the problem with early AV as well as reinforcements.