Sorry you feel this way about the article, to clear a couple of things up, it was written in 16 June 2016. .NET Core 1.0 was not released until 27 June 2016 (after this article).
.NET core has had many changes and releases since then and the nuget.org ecosystem has grown significantly.
I gave 2 examples in the nuget section, Kubernetes and Rancher. The Rancher example is still true (no stable packages) https://www.nuget.org/packages?q=rancher
Kubernetes is very different, but K8S has also exploded in popularity since 2016.
That said, I still feel that PyPi.org has a broader and more stable set of packages for working with popular open-source tools than nuget.org.
With respect to Web APIs, the situation has improved slightly since writing this article.
The point around .NET not working on *nix systems has changed with DNC’s releases. But .NET itself (and the majority of the Ecosystem that relies on it) still requires Windows