Chinese haven't. Yes, Japanese and other asian places have been wearing masks even before COVID but China def did NOT until COVID. This was filmed during the pandemic although I agree she likely was wearing to hide her identity. The fact she even had a mask is proof it was filmed in China during COVID times.
First off the video is from at least 2019 before the pandemic. The mask is to obscure her face not to protect her from something like COVID. Also Asians have been wearing masks for years because of all the pollution. I was in the Philippines pre COVID and people wore masks while commuting pretty often.