Linux and Windows together dominate this market so thoroughly that everything else (UNIXes, BSDs, macOS) is practically a rounding error.
Continuous integration and deployment is all done with Microsoft agents orchestrated by VSTS (Microsoft's hosted version of TFS). Yes we use git
Easy to maintain and no performance issues.
I can approve and deploy a release from my iPad (the website is painful on my phone) by logging into Microsoft's Visual Studio Team Services website.
I won't even start to gush about how easy setting up a build and release pipeline is in VSTS compared to the other tools I've used.
Also with unix servers various bastion hosts and similar "security measures" are minor inconvenience and usually even supported by automation tools, while on windows this usually ends up being major PITA.
There was a time when our net ops team did something and I couldn't Remote Desktop into a server to do something urgent and if course I couldn't just SSH into it where I had to write a quick Powershell script and deploy it via VSTS to make a change. It was ugly.
Besides, I already have sane deployment groups and tags defined by server environment and function. I might as well leverage them.
1) You can install an SSH server on Windows boxes just fine, then use Putty to SSH directly into PowerShell. PowerShell is not a classical shell, but rather a REPL for a procedural, imperative and object-oriented DSL for system configuration and administration based on .NET, with much saner syntax than my beloved zsh. In short, it works quite well.
2) With PowerShell capabilities - I'm a bit fuzzy on the details here, was a long time ago - you don't even need the SSH server, you can issue remote commands from your local PS instance. It required a bit of configuration up front, IIRC, but then you could replace your local session with a remote one with a single command.
So, in my experience - and note that it was probably nearly a decade ago! - Unix-style remote management was absolutely possible and not that much less convenient. And PowerShell is really a solid tool, with easy access to all of .NET and all of the system; the only annoyance I remember was certificate/signature management, dunno if it got any better.
But part of the problem is I have a real prejudice toward local agent based solutions with a central server coordinating everything.