The only thing that lets old tools get rusty is a lack of maintenance or improper storage. Software does not need to suffer from either and plenty of 'old' tools are still in maintenance. Kernels, compilers, file-systems and network stacks originally written decades ago are still in common use today. Flex and Bison are still being maintained and still have major releases. Whether they are still 'state of the art' is another question entirely but they're definitely being used and they are more than ok for quite a few jobs.
> The only thing that lets old tools get rusty is a lack of maintenance or improper storage. Software does not need to suffer from either
1. Yes, you can ruin every metaphor if you over-analyze it enough.
2. No, software has its own "rust" scenarios, like not staying compatible with other ecosystem elements, or simply being different than the current best-practice.
