> I wish the was a way to fix this attitude. So that project maintainers didn’t need to write two page apologies for finishing their thing.
One of the problems is that GitHub is full of OSS libraries where the last commit was three years or more ago and you have no idea (without forensically analysing commits, issues, etc.) whether it's because the project is done or because the maintainer(s) lost interest, had other priorities, etc.
And you have no idea because they haven't said. They haven't told anyone: it's just drifted into an unclear state of unmaintained-ness.
I would suggest rather that what the Moment.js team have done here should be the norm: i.e., clear communication of the situation. That situation, as here, might be "done", or it might be "the thing's only half finished but we don't care enough to carry on any more", or something completely different. These are all good reasons to stop working on something even if they're potentially frustrating for users. E.g., in the "don't care" scenario, people have the option to step in and pick up maintenance, fork the project, or simply not use it.
Doesn't matter: understanding the state of a potential dependency in terms of maintenance and development is the key factor that will enable people to make an informed decision about whether to use it or not.