You're probably mostly right, but note that there is a bit of a "dark matter" issue here. A lot of open source work is done at the behest of an employer and on

You're probably mostly right, but note that there is a bit of a "dark matter" issue here. A lot of open source work is done at the behest of an employer and on the clock but still appears to be a "personal" project. I have worked on many open source projects that would appear to be entirely the work of individuals, when they are in fact working on company time.