I mostly agree. Talented people can often demonstrate that talent across a wide range of situations. But it's naive to expect truly world-class expertise developed over decades to be readily transferable to other areas. It's easy to say people should keep their skills up to date. But if your compensation and reputation is based on a deep understanding of a narrow area that took years of experience to create, it's easier said than done to just learn something new and expect to be compensated similarly.