I like the concept. Are any of us truly irreplaceable? There is surely another people who could do the same thing.
Do things that are important and nobody else wants to work on.
Discussion
Part of irreplaceability is a desire to do that which is useful, but not yet obviously popular. It’s taking a point of view on the future that is not widely consensus and giving it your all because you see something that most people don’t yet.
Great expansion of the concept. Pulling the future in because you see it when others don’t. By the time others see it, you’ll be there with infrastructure built to handle them.