I put to you the proposition that to "Obama", $5 million is chicken feed, that the Obamas have, in effect, access to limitless funds.
His career consisted of poorly paid community organizing and adjunct faculty positions from 1991-1997, when he was elected to the Illinois Legislature. From 1997-2005, he was a State Senator, which paid $69K/year, from 2005-2009 he was a US Senator, which paid $174K, from 2009-2017 he was President, making $400K, and since 2017 he has been unemployed.
On that history, he bought an $8 million mansion in Kalorama, a $15 million estate on Martha's Vinyard, is building a $15 million estate in Hawaii, and he has kept the Hyde Park mansion in Chicago which he paid $1.65 million for in 2005.
It's fair to say that the former President has undisclosed sources of income.
As the article says, the $5M was never intended for Obama’s pocket. As you point out, Obama as access to unlimited funds, so $5M in his pocket would not be especially tempting.
But the $5M was to go to a charity to be named by Obama. Again: not really about the money itself. It’s a shaming tactic. Obama had the ability to effortlessly send $5M to the charity of his choice — AND HE REFUSED. What’s up with that? What kind of person would do that? It’s supposed to make people think about what possible motivation anyone would have to be so withholding.
There is only one answer.