No. You eliminate the old job and move the tasking over to people you already have.
This is how corporate downsizing works.

Only if you have jobs that aren't necessary - or if you're stopping the work by cancelling or delaying projects.

But as I noted upthread, the federal government isn't like that. The overwhelming majority of federal employees (about 72%) work in national defense or security jobs, and we're not going to reduce the scale or scope of those departments. You can't just eliminate 10% of your Border Patrol agents and move their tasks over to the remaining ones. Or your VA nurses. Or your federal prison guards. You can't decide that you're going to just have fewer vets that need health care, or fewer federal prisoners, or fewer Border Patrol arrests.

Again, that's why this is a high-stakes gamble. I suspect the people who formulated this idea imagine a federal worker as a superfluous bureaucrat whose tasks could easily be moved to other people - or done without. But if 10% of the guards in a given federal penitentiary take the retirement offer, you can't ask people in the finance department or vehicle maintenance to take an extra shift in the prison yard.