The EB1 visa exists for these "top researchers", the H1B is being used to suppress wages by increasing labor supply for basic software engineering roles a fresh college grad can easily complete.
Student -> regular dev/engineer -> promoted to lead/researcher/manager (or jump to another company for those positions).
If they didn't come to the US on a student VISA, or H1-B to begin with, they wouldn't have been able to follow the path they did.