From a timely server/service OS reality check
"Three and a half years ago, Mark Russinovich, Azure CTO, Microsoft's cloud, said, "One in four [Azure] instances are Linux." Next, in 2017, Microsoft revealed that 40% of Azure virtual machines (VM) were Linux-based. Then in the fall of 2018, Scott Guthrie, Microsoft's executive VP of the cloud and enterprise group, told me in an exclusive interview, "About half Azure VMs are Linux". Now, Sasha Levin, Microsoft Linux kernel developer, in a request that Microsoft be allowed to join a Linux security list, revealed that "the Linux usage on our cloud has surpassed Windows".Microsoft developer reveals Linux is now more used on Azure than Windows Server | ZDNet
Shocking you say? Not really.
Linux is largely what runs enterprise computing both on in-house servers and on the cloud. Windows Server has been declining for years. In the most recent IDC Worldwide Operating Systems and Subsystems Market Shares report covering 2017, Linux had 68% of the market. It's share has only increased since then."