China was not weak back in the 80s. China was not weak in the 60s. They were an economic powerhouse even then.
Douglas MacArther warned Never fight a land war in Asia".
Its a pity you know so little of the PLA military. I could point out the bloody nose they got from thinking they could waltz into Vietnam. I could point out that to this day they have so little navy worth caring about tha they are essentially land locked. from from Wiki:
Ronald O'Rourke of the Congressional Research Service wrote that the PLAN (Peoples Liberation Army Navy)"continues to exhibit limitations or weaknesses in several areas, including capabilities for sustained operations by larger formations in distant waters, joint operations with other parts of China’s military, C4ISR systems, anti-air warfare (AAW), antisubmarine warfare (ASW), MCM, and a dependence on foreign suppliers for certain key ship components."
I could point out that one of the major reasons that they have never posed a real threat to Taiwan has nothing to do with the US and everything to do with their inability to actually move troops across the strait without them becoming the most drowned army in history due to Taiwan weapon systems and ... wait for it ... lack of landing vessels to even put in the water.
Take then the modern PLA and start turning the clock backward and you will see that China has had a second rate military going back ages. Sure to meet them on their own ground is a bad idea, but mostly due to there being no reason to do so. The fact that they themselves didn't learn their own lesson is proof enough that their military has been more about kowtowing to Party bosses that practical military thought. Saying they were strong militarily in the 60's-80's means you have to cherry pick your sources pretty hard. It is like saying the Soviets had a huge impressive military in WWII. Sure they did, if you discount the 8.7 million men it chewed up to grease that machine of war.
The rest of your points are about as bad, but I am not going to go on at length about them, however in short - Air-Sea as a concept before WWII? I guess, but without widespread wireless it is just coordination of meeting times and attacking set pieces, and bad coordination at that, not real Air-Sea - The Soviets collapse being seen before it happened? Yeah, we knew, but there was good reason to believe that it was going to go down in a blaze of glory, and not the quiet self collapse it did, very, very few saw that, this guy did. Precision weapons by your definition date to the creation of organized militaries with pikemen and slingers. No, what he did was to see the need to put the firepower of a 2000lb laser guided bomb in the hand of one man. The only person to even come close the concept might have been Heinlein in Starship Troopers, and well we are trying to duplicate the rest of that book as fast as we can. Add into this his insight into drones prove that he was worth every cent that was spent on him and the loss of his office will make the Pentagon as myopic and short sighted as big US business is about future needs and long term investments.