Re: Cost is the smaller concern
“Ultimately, open source allows you to be in control of you own destiny.”
Strictly speaking that's also true of closed source, but it just might be more painful to change one's destiny... The important thing is to use open standards for one's application / system development so that one can very easily change one's destiny regardless of the open or closed nature of the underlying OS. Development of a classical Win32 app is locked in to Windows. Use Qt, any decent Web platform, etc. and then you have true freedom. It's interesting that MS now seem to understand this; official blessing for Mono is at least some evidence of that.
Open source with no support merely makes one solely responsible for one's destiny. Buying support from Ubuntu or RedHat or someone simply puts one back in the same position as when using closed source (reliance on someone else), but with more options.
Don't get me wrong; MS are steadily making their platform highly unsuitable for many enterprises where privacy is a key requirement, like the NHS. It's a good thing that people are taking a serious look at an alternative. So long as they dump systemd.