It does not sound like a full retirement for Bill Marriott, but rather a lessening of responsibilities. He will be executive chairman, which is a lot different than non-executive chairman. Most CEO's who step down and become chairman of the company are non-executive chairmen (no longer an employee), but an executive chairman normally means that the individual will remain an active employee, probably working closely with and advising the new CEO on a daily basis.
Funny thing is that when we would stay at Ocean Pointe, I would always see in the activities sheet "Friends of Bill W closed discussion group". I thought this has something to do with John Willard (Bill) Marriott. It wasn't until we were on our last cruise and saw on the activities sheet "Friends of Bill W" did I decide to actually Google it and found out what it was really about.