As we are heavily dependent on 3rd party JS libraries and some of them are no longer actively maintained by their respective authors (Last commit was approximate year ago).
Some of the core libraries which are no longer actively maintained are,
wcDocker is, as far as I'm aware, the only library of it's kind. Unless something else has surpassed it in the last couple of years, there's nothing even close in functionality to it. aciTree was in a similar position, though Joao and team think there may be other candidates now.
As for Backbone/Backgrid/Backform, I don't know. Backbone could maybe be replaced with React eventually. Not sure about the others.
In any case, this is likely to be a problem on an ongoing basis - and I think we need to consider the future on a case by case basis when necessary. It may mean moving to a different library, or it may mean forking components, or it may be the upstream may have not had any commits for a long time simply because there is no development happening right now, but bugs may still be fixed.