Visual Studio for Mac had its roots in Xamarian Studio, which had its roots in MonoDevelop. Each one has always been a rebrand of the previous product.

(Edit: I forgot to point out that Visual Studio for Mac never appeared to be a port. It always appeared to be a "clone" of Visual Studio with a very similar UI.)

They've always been rather buggy and unstable compared to Visual Studio on Windows. They were a nice way to do C# on Mac without needing to load a VM; and for the last few years I really appreciated that C# was getting "first class" support on Mac.

I hope C# works well under VS Code.