I think Shanghai has partly been a test chamber for coexistence policies. China can’t stay locked down forever, I haven’t gone home in 3 years because of how ridiculously hard it is, international travel is basically dead, hell even intercity travels. Shanghai is one of the richest cities with the best facilities and also liberal enough to attempt coexistence, so naturally they are the ones testing the waters. Death rates has been very low too due to the mild nature of Omicron, so that’s not entirely the worry. In any case, China needs to open up, and opening up means a wave is gonna hit sooner or later, and Shanghai is braving that wave for the whole country to observe.