There is no Shanghai exception for lockdown as a scientific policy, just like there is no Swedish exception. To decide if a policy advertised as based on universal biology is working you need to evaluate all the evidence, and cases where it doesn't work either disprove the theory or require refinement. As nobody can come up with a plausible refinement that means it's disproven.
As for your belief that 9/10 worked - please. Please! This is a tiger-protecting rock fallacy. Yes if you wear a rock around your neck, more than 99% of the time you will not be eaten by a tiger. The arguments that lockdowns work are all forms of this type of nonsense when examined. Correlation doesn't imply causation, you need to have very compelling evidence to show causality and "sorta overlaps sometimes, maybe" is not evidence of anything because people epidemics have natural cycles and governments tend to trigger lockdowns as they come up to their peaks. That doesn't mean the peaks are caused by lockdowns and it's the exceptions where they have no effect that prove this.
What's your basis for saying that lockdowns don't reduce spread? They do dramatically affect spread - that's been seen in every country. It's almost impossible for them not to affect spread. The virus propagates from person to person, mostly by them breathing the same air. If you reduce contacts between people, you reduce viral spread. This is about as well established as the statement that things fall.
A lot of people commenting here are going on the basis of their experiences in countries that had on-again, off-again lockdowns, but in which the virus was largely allowed to spread. Yes, if you do a partial lockdown during the peak of a surge, and then start reopening once the surge starts to subside, you'll never eliminate the virus.
China's strategy has been completely different. It locked down hard in early 2020, and completely eliminated the virus within its borders. It then shifted attention towards stopping the virus from getting back into the country, by requiring international arrivals to quarantine. It also built up extremely good contact tracing systems, to identify and contain new outbreaks before they could spread widely.
That has worked remarkably well for over 2 years now. This is the first time that Shanghai has had to lock down since early 2020.
So yes, it's obvious that the overall strategy that China has followed is effective, and it does involve lockdowns, along with other measures like border quarantine and contact-tracing apps. This isn't a tautology. It's just an observation: there's a strategy that a massive country followed, which obviously worked.
The government is pushing for old people to get vaccination. Old generation in China are not getting vaccinations because they worry it may have side effects. As far as I have heard, the government is pushing it by linking some money (old people get some government money for special occasions) with the vaccination.
Overall, the country will have to accept the fact that the virus will spread, especially if they want to open borders. The current strategy is to contain it as much as you can. Once it open up, it will have a peak similar to Hong Kong, maybe hundred of thousands of old people will die.