We obviously disagree on this point, although "the vast majority of people who know about software" is a fairly vague qualifier.
The fact that many software projects distribute under licenses that comply with the OSI's definition is not particularly relevant to my argument anyway. I'm not talking about people distributing the software, I'm talking about the large number of people I am aware of who think of "open source" strictly as software where the source is available.
The US government examples aren't particularly relevant either. A small number of people make those decisions, and there are legal ramifications for them in how they define things, so I'm not at all surprised that they define the term that way.
As I said elsewhere in the thread, I was not arguing that people who use "open source" as equivalent to "source-available" are right. Mainly I'm arguing that there is still a very large group that see it that way, and that the meaning of the term is far less settled among people who use it than some would like it to be.