I read the whole blog post disagreeing with almost everything right up until the end when I read:
"This is the one shining negative here: .NET stunted my knowledge of HTML/CSS/Javascript."
This is the whole point of the blog post. And this is in fact true. But terminology that is not pointed out is that ASP.NET WEBFORMS are what "stunted" your knowledge. WebForms made developers oblivious of how the web actually works. .NET, C#, or VB.NET isn't the problem.
Also, living in a Microsoft world can be insulating, but only if you aren't looking for a better way. "Alt.NET" was really a belief in outside the box thinking.
Focus on Principles, Patterns, and Practices. Ask yourself "why" regarding everything. Understand the problems and solution a technology/pattern/framework/library solves rather than blindly using said solution.