I really disagree that authors have a general obligation to do anything with their code, at least as far as support is concerned. If somebody signed up formally to be a committer or made some other explicit commitment that's of course a different matter.

If there's an implicit obligation, it seems to me it's on users, not authors. If you really need something changed you should fork/fix it yourself or talk somebody else into doing it. That right is baked into every major OSS license.