I wonder what percentage of the Linux users making these reports are already professional IT people in some capacity. I'm not convinced that it's "the open source way" causing this to happen, but instead suspect it's "the experienced engineer way".

You could argue that these two are very closely related things.

That's exactly what I am arguing. If you have a Venn diagram of IT professionals and Linux users, I'm sure the overlap would be a lot greater than that of IT pros and Windows users. It follows that a Linux userbase is where you'd see a disproportionate number of people filing exceptional bug reports.