Yeah, it can be used commercially, but it's the restrictions in functionality you run into that can cause problems - as an example it doesn't allow for plugins, which means no direct integration with version control. That's problematic if you're freelancing in a team with more than a handful of engineers. It's also…
Well that's not entirely the case, while it may be free to get started with programming a game, most professional programmers have a set of go-to plugins that aren't free (unless you're a student, a lot of companies seem to love giving handouts which is awesome!) Some plugins like ReSharper for example, can range from $200…