For a computer company with so many billions in the bank it's amusing how Apple has married itself to the iPhone. Why not try to leverage the relatively secure

For a computer company with so many billions in the bank it's amusing how Apple has married itself to the iPhone. Why not try to leverage the relatively secure walled garden of iOS to open a business selling hardware and software to enterprises? Why not make Unix servers with distinguishing features? Management could get away with it while they were surfing the iPhone wave but it was always obvious that it wouldn't last forever.