China does not recognize patent law, therefore they could not have stole anything. I am all for recognition of one's discovery but the patent law in "the west" went too far and is more a retarder rather than accelerator of progress.
> In 1985, China acceded to the Paris Convention for the Protection of Industrial Property, followed by the Patent Cooperation Treaty in 1994. When China joined the World Trade Organization (WTO) in 2001, it became a member of the TRIPS agreement.
"Article 42 The duration of an invention patent shall be twenty years, the duration of the patent for a utility model or design shall be ten years, counted from the date of application." [1][2]
[1] http://mg.mofcom.gov.cn/article/policy/201910/20191002905592...
[2] http://www.npc.gov.cn/npc/c30834/202011/82354d98e70947c09dbc...
Here, an actual IP theft (as in "files on a USB stick") is involved. Not just violating patents.