Not quite. It's easy to create a duplicate of your metal key, and many people do exactly that to avoid a situation where they lose it and have no way of opening their door. The fact that you can't do that with USB keys is my biggest gripe with them. I understand that inability to copy even if you have physical access to the original has its security advantages, but 1) most things don't actually need that much security, and 2) it could still be done by e.g. allowing you to buy them in premanufactured batches where all keys are identical.