Actually there is! It’s not perfect or exactly structured how you’ve shared, but this forum is built on Discourse which has been refined over the course of decades, serving thousands of communities.
Built-in to Discourse is the Badges and Cheers system, which gives points for contributing to posts, solving issues with the “solved” plug-in, and many more. @Sheyda did a great write-up about it here:
Additionally, check out the “Trust Level” system, which rewards users for participating in meaningful ways, by “graduating” to increased trust levels. You start at level 0, and can get all the way up to level 4.