Interesting stats here (including that in 2009, approximately 80% of software sold in China was pirated)
https://en.wikipedia.org/wiki/Usage_share_of_operating_systems
https://www.netmarketshare.com/operating-system-market-share.aspx?qprid=10&qpcustomd=0
https://www.netmarketshare.com/operating-system-market-share.aspx?qprid=10&qpcustomd=1.
If you’re insinuating that the market dominance is due to pirated software, I would point out that most major marketing firms account for that bias in their numbers. The raw data is often much higher.