What prevents Cargo from adding `[bench/bin/example-dependencies]`?

To put some of my comments in a different way, if someone where to try to move this forward, I would recommend looking at the larger landscape of potential dependencies tables and work on a clear picture of why this is the route to go along with a high level design, including

• comparing with designs as wide as enable-features (including looking at why it was rejected and related discussion)
• Registry index
• cargo add / cargo remove
• Interaction of existing and new tables