> Certainly that depends on the nature of the software. For instance, I don't expect some header-only library that does what it's supposed to do to ever need updating.

If it's a headers-only library in a language such as C++, if the project is not dead then the very least anyone would expect from it is being updated to support any of the modern C++ versions.

Also, if the project is actively maintained then there is always a multitude of low-priority issues and features to address.

Being FLOSS also means anyone in the whole world is able to contribute anything. If no one bothers to do so, that is aligned with the fact the project is indeed dead.