I would probably agree with that. I don't think people realize how much Lee did with very little. He was tasked with defending the Confederate Capital, but he still fought an aggressive war that kept the Army of the Potomac chasing its tail. His aggressiveness helped sell the idea that the Army of Northern Virginia was larger and stronger than it was. After the surrender, many Northern generals were shocked to find out what a scarecrow/depleted force had faced them from the defenses at Petersburg.
Also, the South came a lot closer to winning than people think. All they had to do was keep up the war until the North tired of it. A "draw" in the war would have meant a victory for the South because they would have achieved their independence. After the bloody battles of The Wilderness and Spotsylvania, war weariness was setting in among the northern states. Had Lincoln lost the election in 1864, it's quite possible the North would have ceased fighting.
I don't think we will ever really "get" the loyalty some felt to their state over their country. Lee said that when Virginia seceded, she took him along. Had Virginia not seceded, he would have stayed with the Union. Too bad Lee did not stay with the Union. Imagine Lee in command of Northern forces at Antietam when the knowledge of the rebel army splitting into separate parts became known (due to a rebel officer dropping a map that showed the disposition of the Southern forces. The officer had wrapped some cigars in the map.). He would have crushed the rebellion then and there (as McClellan should have).
Of course, when we try to decide great generals, we have to take into account the times in which they lived. Maybe a 19th century general would fail in modern times, and vice versa.
It’s so funny how the American Revolution is virtually the same. Even in your description.
Washington doesn’t get the credit he deserves. His situation was MUCH worse than the noted “rag-tag” Confederate army. He dealt with much worse, including trying to ensure Congress had a say in how the war was run so he was not a military dictator. Once Washington threw off that concern his natural genius becomes even more apparent. And it’s not all due to the French, despite constant refrains that it was. They hardly did anything besides supply. Washington had to hold it together with almost nothing, and wear them down also. He did so.