That's arguable but it's not what this argument is about. This argument goes far far wider, into issues such as liability, quality, collective usability and security, just to name a few. It's about governments agreeing a way forward... hence legislating rather than leaving it up to successive governments to make decisions on an ad hoc basis.

In other words, I think, governments shouldn't be mandating the use of open source either. All they need to do is mandate that software producers take liability for any faults in their products OR include the source code.