It will be interesting to watch how Andy Jassy as head of AWS (dealing with building out data centers, SW partnerships, API uptime, negotiating with Intel, designing Graviton CPUs, etc.) will be able to transition to such things as Prime Video content licensing discussions and goal setting for Whole Foods and the nuances of warehouse distribution labor disputes.
As a founder of Amazon - having built Amazon from nothing, Bezos probably had certain in-built persona and gravitas which probably helped with leadership talent acquisition and vision setting in all domains of the business universe. The opportunity to report to Jeff Bezos was probably a huge selling point - no matter what industry you were coming from.
Its interesting Amazon never attempted to give Andy Jassy a trial run as a public facing COO running both sides of the house.