My perspective: the existing building industry is a catastrophe of disposable buildings (design life of 25 years sound familiar?), unmodifiable proprietary systems, forms that suit a purely extractive economy (spreadsheet architecture) and sheer ugliness. In a sense, I don't really care that these buildings are designed in non-free software - I don't want them to be built at all.
Existing proprietary BIM software has been developed to enable a system that is eating the planet, (and I know we are all embedded in this system, it pays for my daughters' violin lessons etc.) just switching this system to free software is not just really hard - proprietary software generates money that funds a vast marketing machine that will be used to turn users away, not to mention the patent system that will kill any free alternative if it ever becomes a genuine threat - but even if we win, the world still loses because the system has only become a little bit more efficient.
If the existing system is prepared to fund our free alternatives, that is great and we should jump at the chance, and maybe that is all that we can achieve, keeping the door open even if it is only a little bit, but we must keep in mind that there is so much more to be done.
We need an understanding of what is wrong with the industry, and what people need from architecture to lead fulfilling, non-destructive lives. We should create the tools that are needed to do this because the AEC industry won't.
So the Opening Design model of doing architecture in the open, entirely in a public git repository, has to be part of this, as it lowers barriers to entry and shares knowledge about how buildings are actually built.
But we also need a vision of what we want from 21st century architecture: Who builds it? Who designs it? Who owns it? How do we make it last for centuries while still being adaptable for uses we have never thought of? What does it need to be made of so as not to eat the planet? How big is it? Is it cities or rural? What does it look like? And if this vision is different from that of the industry we find our selves in, what tools do we need to create to change it?