Why didn't the Kuomintang defend the Yangtze River?

The War of Liberation, the Battle of Crossing the River? The Yangtze River defense line is more than 2,000 kilometers from east to west, and the strength is simply not enough. We don't know where our army will attack.

In fact, since the defeat of the Huaihai Campaign, the Yangtze River has been doomed to fall. The best way to defend the Yangtze River is to organize a powerful mobile corps on the north bank of the Yangtze River and use the Yangtze River as a backup supply. Therefore, there is a saying that "he who defends the river must defend the Huaihe River".