Earlier quoted context omitted.
that's maybe the second or the third most important factor. the first is aggressive marketing that microsoft does for its products.
That unfortunately hasn’t helped C# become more popular outside of Microsoft legacy shops even when it did go cross platform and open source.
Actually I thought of using C# a few months ago, and I was like "Oh wait, does it even work on other platforms than Windows now?". Sure I'm not a C# developer, so I'm not up to date on C# news, but that's an issue if your goal is to drive adoption. Everyone that has heard of C# should know that it's now cross-platform.