Before getting into an argument of MS vs. the world let's take a step back.

What are you goals? Do you want to get a corporate job? Do you want to start or work in a startup? Also, where do you live?

There was a related thread a while ago: https://news.ycombinator.com/item?id=8159427

To make a long story short, my personal opinion is that you can have a very fulfilling corporate life focusing completely on MS technologies. In some countries/regions more so than in others. For example, you won't find a lot of MS-based companies in Silicon Valley, but I've been to a couple of European and Asian countries where the majority of businesses seem to heavily favor the MS stack. An MS stack is almost always the wrong choice for a startup though (and you've mentioned some of the reasons).