I guess maybe it could apply to some niche cases of locally run software like photoshop, though I’d be be shocked if the marginal gains of a bug bounty program could justify the massive cost of implementing a mod system like this for photoshop.

But the fact is that most software in the world doesn’t work like Skyrim. Large parts of most software runs on servers or on locked down mobile operating systems where modding systems are not possible.

What you are proposing kind of already exists for web frontends in the form of browser extensions, but having worked on several apps for which an ecosystem of browser extensions sprung up, my experience is that there is no simple way to port these features to the main product. For security and QA, every line of code needs to be vetted anyway, and then “translated” into a form appropriate for the existing code base. At most, they just validate demand for a feature or bug fix.