libyears
I've encountered https://libyear.com/ & https://github.com/hkalbasi/cargo-libyear . I agree with the concept. It is a raw simple number that can be easily tracked over time, and is something a manager can understand.
It occurred to me that cargo-unmaintained is doing almost all of the same underlying effort, and could likely spit out the number of libyears for an entire project very easily, and could report on dependencies with high libyears.
I'm going to have to look at this more closely.
This is pretty interesting. Thank you for sharing it. I just worry that it would be feature creep.
If it could be enabled with Cargo feature (e.g., cargo install cargo-unmaintained --feature=libyears), I might be open to it. But I worry it would require a large refactor.