Not only building. Also tinkering, using, testing out of curiosity, etc. There are around ~30 million software developers worldwide today (source: googled it).

Not only building. Also tinkering, using, testing out of curiosity, etc. There are around ~30 million software developers worldwide today (source: googled it). Around ~7 million of them are registered users of Github (source: googled it). 1M+ seems likely to me. BTW, I appreciate that you preceded your comment with "Pedantry time!" -- nice gesture :-)