Merely 11 years ago, China did not have enough helicopters to deal with the 2008 Sichuan earthquake. The entire nation had an inventory of around 400-500 helicopters, that included police and civilian owned. That number was said to be even lower than the city of São Paulo in Brazil at the time, it would be pointless to compare it to any nation. Fewer were capable of heavy lifting or flying at the high attitude of Sichuan. And I still remember to the embarrassment of PLA that it took over 10,000 personnel and 10 days to find a missing Mi-171 in the woods during the rescue operations.
Glad to see so many helicopters in the sky in one picture, and that shocking weakness is now history (well, kind of, as they still lack heavy lifting capabilities, and the production capacity has room for improvement).