This is completely inaccurate. Zhang Qingying's rudi was a big vault. She proved it at trials, it scored much better than the FTY's they instead had to bring. Her beam was consistent throughout season and had higher scoring potential. You're twisting things by trying to say it's likely she would score a 12. All the data says she was likely to outscore both Luo Huan and Ou Yushan.
OYS's floor is replaced by Qiu Qiyuan's, exactly as I said. Qiu was consistently scoring 13.5 this season, she never missed a routine and has great choreography and performance quality.
There were no "more inconsistent" people. Again, Zhang Qingying had better consistency on Beam (there was literally talk of Luo Huan possibly being pulled from the team last minute b/c of missing routines at the last internal test) and Du Siyu's "inconsistency" on Bars was merely because of trying upgrades, which she could have dialed back exactly as Zhang Yihan did.
If you want to live in the theoretical world where they hit all of their routines, then you also have to give that to other countries, who were not perfect themselves. This team was NOT guaranteed a medal if they simply hit.
It's a strategic mistake to take a team with such a hole on vault when you're not gaining any higher scoring potential elsewhere, and to bring someone like Luo Huan for middle-of-the-road routines without any real upside. They left more than 2 points on the table, without gaining any higher amount of extra consistency. They honestly made their level of consistency worse by taking Ou Yushan.