All of this has absolutely, truly, nothing to do with rewriting something in Rust. You could also rewrite the same library again in C and have the exact same conundrum.
Also, people build dependencies on effectively “hobby” projects all the time. Open source in particular works well this way because the dependents have a good reason to contribute back; the users become stakeholders and contributors. The same may not be true of internal software, but again, this has little to do with the concept of rewriting something in Rust.
This is really diverging into a discussion that has nothing to do with the original paragraph I addressed.
Also, people build dependencies on effectively “hobby” projects all the time. Open source in particular works well this way because the dependents have a good reason to contribute back; the users become stakeholders and contributors. The same may not be true of internal software, but again, this has little to do with the concept of rewriting something in Rust.
This is really diverging into a discussion that has nothing to do with the original paragraph I addressed.