I stumbled onto this.
The Vanguard Group, Inc.
Was founded by John C. Bogle. I found an article from the late 90's. John Bogle Rejected an Offer To Stay on Vanguard Board. But ''In a surprise ending to an embarrassing public spat between Vanguard Group founder John C. Bogle and the fund company's directors, the board agreeded to 'waive a mandatory retirement rule' so Mr. Bogle could do what he has said he wanted all along: stay on the board. (article)
Could be something or nothing but what is concerning is the 'the why' the waiver.
https://www.wsj.com/articles/SB9377767445929564