Windows may be the post popular desktop/laptop software in the world, though I would argue laptop dont have that much headway anymore.. At my 80k employee shop, vast majority of laptops are now Apple, but thats fairly recent development over last 6 years or so.
It is not however the post popular Server OS in the world, for many reasons.. Licensing Costs, Stability and Uptime are the main reasons Windows Server looks poor next to a unix server.. Ive got a linux box here that has a 633 day uptime, and its fully up to date on all security patches... any fully up to date windows server will have a max uptime of a month or so with the required reboots.. If you know what your doing in Linux you can even patch the kernel without rebooting.
Windows does work fine as a server os, Ive got Clients with them doing very critical stuff from military communications (US Military LOVES Windows) to wall-street auditing, however there systems are rather more complicated than they should be so they can provide the desired levels of availability and reliability. Not to mention they all are on extremely hardened networks to defend the servers from any harm.
Windows Servers are most often chosen because of Software requirements force no other alternative,
BlueIris is worth running a dedicated Windows Server for.. most of the other NVR solutions on the market are junk in comparison if you want to mix-match camera manufacturers.
And then there is the age old saying, nobody ever got fired for choosing microsoft...
largely because you can always shift the blame for all your problems on them
