You must be injecting crack directly into your frontal lobe if you think that the creator of the world's third most important programming language being asked an algorithms question (unlikely) and failing it (entirely possible) means that he's unqualified to do "foundational work."
I had a Nobel Prize winner as a physics professor in college who got three successive different wrong answers when attempting a freshman physics problem in office hours. That doesn't mean that physics isn't the right place for him to work.
I had a Nobel Prize winner as a physics professor in college who got three successive different wrong answers when attempting a freshman physics problem in office hours. That doesn't mean that physics isn't the right place for him to work.