Nobody disputes that Ms. Wilsey, the daughter of a United States ambassador and widow of a real estate tycoon, who left her an estate valued at around $300 million upon his death in 2002, accomplished what the city of San Francisco could not: Under the museums’ director, Harry Parker, she raised enough money to build the new de Young in Golden Gate Park after the original 1921 building was declared unsafe and demolished, drawing heavily on her society connections as well as on her own bank account.

When the de Young reopened in 2005, Ms. Wilsey put her name on the biggest atrium (Wilsey Court) and her dogs’ names on the lobby walls reserved for donors (Eliza Norwich Terrier Wilsey, Serena Maltese Wilsey and Sparkle Maltese Wilsey). That was the same year her stepson Sean Wilsey published his withering memoir, “Oh the Glory of It All,” criticizing Ms. Wilsey as the “evil stepmother” who lavished more attention on her emeralds and diamonds than on him. (Ms. Wilsey dismissed the book as a combination of outright lies and “fantasy.”)

At the end of 2005, Ms. Wilsey brought in John Buchanan as director and developed an unusual niche in the museum business: importing major shows from Europe (often at a steep up-front cost, to be recouped by high ticket prices), including Picasso paintings and masterpieces from the Musée d’Orsay, as well as fashion exhibitions that drew a new crowd.

“I specifically hired John to go out and get me the blockbuster shows,” she told me in 2014, describing how they wined and dined potential lenders in Europe. “John and I could sell ice cream to the Eskimos.”

Attendance across the two sites broke the two million visitor mark for the first time. But Mr. Buchanan died of cancer in 2011, and the board did not find a replacement until 2013.

Many say this is the period when Ms. Wilsey essentially assumed the museum director role herself and overstepped traditional boundaries by firing several longtime staffers. (Ms. Wilsey denied any role in the staff firings and called the institution’s operations “totally transparent.”) The museum bylaws, already changed to abolish term limits for the board president, were amended again to give the board president the duties of chief executive officer.