alt Hacker NewsOf the publicly available sources I think CloudFlares Radar is one of the better ones. Silver linings of having such wide dragnet on the internet. It puts Linux market share at 3-4%, with some regional variance
https://radar.cloudflare.com/explorer?dataSet=http&groupBy=o...
Fun tidbits, Finland is at ~10% (!), and Germany at 6.3%.
This was probably a lot more true in the past but Linux users tend to be more privacy conscious and do things like spoof their user agent, so this is almost certainly an undercount. You basically used to have to do this to browse the web before Firefox became one of the dominant browsers.