the West did not go Zero-Covid, this means that any quarantine in your country due to global exchange of people and goods will still have new variants getting inside your country as soon as you end it

This is the biggest issue. Zero Covid has little end goal unless everyone else was doing it. It's effective still, but it is a delay of the inevitable because people will slowly become more and more pissed (the Chinese population is not free from the same reactionary thinking that drives Covid policy opposition elsewhere) and you'd be forced to give it up eventually anyway.

But China I think did do a fantastic job balancing it out. Pretty much everyone who wanted to be vaccinated could be at that point multiple times over and the variants while still deadly are better overall.

I do think they changed faster than they should have but I get it's pretty difficult to soft landing especially when the anti lockdown forces were growing and you wanted to put an end to it.