That’s an interesting challenge, but I’m not sure how you’d measure it objectively. Suggestions are welcome though.
It is clear that Go was designed to be idiot-proof, but I think the increased semantic information of Rust will win out on a team of reasonably skilled engineers.
Your es6 example missed the most important part of es6 — Map. If you find yourself using hasOwnProperty in es6, you’re almost certainly doing it wrong.
Here’s a more idiomatic JS example (from memory, so may not be 100% correct). This also demonstrates the new destructuring syntax.