Two out of three developers who answered a survey on a self-teaching site are self-taught. I see this is yet another article assuming the SO survey is represent

Two out of three developers who answered a survey on a self-teaching site are self-taught. I see this is yet another article assuming the SO survey is representative of developers in general. It is not. It is representative of people who use Stack Overflow heavily enough to see and click on a survey link. Clearly there's a lot of interest in finding out what is true of developers in general: What languages do we prefer? What's our educational background? What are our demographics? It would be great to have a survey that would answer such questions. This one doesn't.