Convincing people to offer others programming help on the internet isn't a special accomplishment of SO. From usenet to modern mailing lists to forums to IRC, there are tons and tons of thriving venues for it. The gamification might have helped SO's popularity some, but taking time out of their busy lives to answer others' questions was alive and well.

SO is a dangerous trash heap. It doesn't encourage helping people make good programs; it answers extremely literal questions. Speed of post is important. Style of post is important. Blatantly wrong answers are upvoted by people who don't know what they're looking at when they are early, indicating that vote count isn't telling ever. Doing anything but answering a question completely literally is treated with extreme hostility. These sorts of things have gotten worse with time.

The community relations are bizarre. Active members of the community buy into cheap salesman lines by the owners that are meant to favor the owners. The idea that the community can direct itself is thrown around as if it wasn't blatantly untrue.

Yes, an incredible people jump at the chance to help strangers. SO didn't invent that, they're just one of the more popular current hosts to these people. It's distasteful to act like it started by wondering if such people exist.