I agree. Plus most of the code is written by a single person, and while most first authors are relatively responsive on github, they soon get overwhelmed with o

I agree. Plus most of the code is written by a single person, and while most first authors are relatively responsive on github, they soon get overwhelmed with other projects, manuscript responsibilities, and job hunts. Coding and its maintenance is only a small part of an overworked and underpaid academic's responsibilities, so frankly its understandable. There's also a good chance that they are no longer employed at the same place a few years out.