Linux runs on the majority of webservers. If you were to look at the usage breakdown of servers in general, Windows would probably be more common, by what I’d imagine would be a wide margin. I’ve never in my life seen an enterprise run anything internally besides Windows Server with Active Directory and a majority fleet of Windows workstations. There isn’t really a viable alternative.
Linux is definitely a go-to as a web server, load balancer, or some other appliance, but behind that a lot of the time are a bunch of Windows Servers as well.