I must say, for all the dumb crap their politicians spew, the American policy makers (the actual behind the scenes people who formulate their policies) are quite aware and pragmatic. Their analysis on China and the distinction that sets it apart from the rest of the developing world is very on point.
I wouldn't be surprised if they weighed all pros and cons over and over and came to the conclusion that China's growth is just very unique and one of those impossible to achieve odds that no other developing country could reach nor any of the developed countries could contain or halt. Thereby they came to the conclusion that only a kinetic war against China with all their vassals in tow could stop it for good.
The date they planned it was probably around 2020 when China was strong enough to be scary but not strong enough to defeat the US in the Pacific. COVID as a bioweapon was designed to weaken China further before they came to deal the final death blow by direct military action. This could very well sync in with the heightened tensions in 2020 when China put all of her theater commands on high alert believing an attack by the US was imminent, requiring Milley to call either Gen Qu or Gen Wei to say that the US wouldn't launch an attack without informing China beforehand.
I think there were 2 reasons why they couldn't go forward with their plans, first and the most obvious one was they didn't count on the virus spreading and becoming a global pandemic requiring not only the US but all of their vassals along with the rest of the world to focus on dealing with it, including financial grants to their populations and purchasing medical equipments from China. Secondly, the test of FOBS that took place around that time which as per their own assessments "managed to circumnavigate the globe before releasing a Hypersonic vehicle which missed its intended targets by only a couple of metres." These events might have deterred them and gave China crucial time to get even more powerful by building even more J-20s and AWACs, sensors, ballistic and hypersonic missiles etc. Either the genie is out of the bag and they have accepted that they might have missed their chance to take China down forever or they will go back to the drawing board and try again a few years later, remains to be seen.