Anthony Fauci has been at NIH since 1968. That might be a rare example, but long careers do happen.
The career is long certainly but I think we all believe we are evolving in our careers. No one here would want to be accused of working in the same way or having the same knowledge in year 1 of their career compared to today.
The CDC has a lot to make up for - it also started in 1946, after tuskegee was started