A few things people need to realise about these "War Game", having been involved in Military Intelligence myself, I was part of some of these "War Game" which I know first hand
1.) War Game ALWAYS start with the worse scenario, in this case, US Bases in Asia and Hawaii was attacked by Biological Weapon and taken almost all of their combat power out in the opening salvo. Call it "Pearl Harbor" effect or whatever you want to call it. nobody runs war games with you start with an advantage. We all know how to fight when we are winning, what these war game drill in is to try to turn the bad situation around.
2.) In these war game, US would lose up to 80% of the Pacific Airforce. While that's a lot but that is roughly 40% of the entire US Air Force strength, while not counting the reactivation of Davis-Monthan AFB which will patch up to 20% strength with the older reserve F-16 and F-15 aircraft back into service.
On the other hand, China would loses upward to 70% of their national strength. That mean after this war, US would still be around 60% strength after the reactivation of the reserve, while PLAAF will down to 30% or lower strength. Which it ceased to be an effective force.
3.)Almost none of these War Game I known of (And I know a lot) have resulted in Chinese occupation of Taiwan. In fact, after Battle of Snake Island in the Ukrainian war, I would say it's nearly impossible for any modern force to completely occupy an island.
4.) This war is going to be fought in between China and Taiwan, it would be naive to think US/Taiwan and allies will not attack Chinese infrastructure in this war, I mean, people can think like the Russian and think "I invade you and your land is all game and my land is off limit", nobody else think like that, certainly not the Ukrainian, and we can assume Taiwan would attack Chinese mainland, and seeing Taiwan as a more competent force than Ukraine, you are looking at wholesale destruction of Chinese East Coast.
While material loss with the US can be replace as US most likely would not be affected as Chinese Missile and Air Attack most likely will not reach US Mainland barring nuclear option, China will have a difficult road to recover from this.
5.) I can almost certainly guarantee you if and when US get involved in this war, US will NOT be going in alone, unless US started this war (even if they did, there are still some countries will follow US down this path) Which will most likely alter the outcome of a heads-up war game.