As it turns out, the former president’s ears really do protrude outward, swooping up a generous hodgepodge of genres and styles: hip-hop, rock (“dad” and otherwise), R&B and more. My favorite entry comes in his 2017 list, delivered as a nerdy asterisked addendum: “Bonus,” he writes. “‘Born in the U.S.A.’ by Bruce Springsteen (not out yet, but the blues version in his Broadway show is the best!).”

Regardless of any feelings about the recent leader of the free world transitioning into a Nick Hornby protagonist, Mr. Obama makes a knockout music critic. Putting together these year-end lists is no picnic. When staff positions compelled me to assemble them, the task reliably bedeviled me. Year after year, I would cavalierly shun entire musical movements, turn my nose up at anything hinting of trendiness and punish personal favorites if they fell short of masterpieces.

A sentimental streak tripped me up: If a singer and his entire audience seemed on the verge of succumbing to old age, the artist was pretty much guaranteed a spot near the top of my list. In these faults, I was not alone; year-end lists tend to expose any critic’s flaws.

Mr. Obama avoids such nonsense. While he retains some generational tics (he’s sticking by U2), his taste mostly tilts toward fresh voices, an asset that eludes many professional critics: Meet the semiretired law professor with two kids in college, rapidly graying hair and a willingness to welcome Young Thug into his life. Through Mr. Obama, I have been hipped to the Congolese singer Jupiter Bokondji, prodded to give a closer listen to the hirsute country star Chris Stapleton and reminded of the unadulterated joy of Cardi B, J Balvin and Bad Bunny’s “I Like It.”

His prose, always electric, assumes an extra whiff of fire when applied to music. “American history wells up when Aretha sings,” Mr. Obama wrote to The New Yorker in response to an email query about the artist in 2016. (True to rock critic cliché, he was then working a day job.) “That’s why, when she sits down at a piano and sings ‘A Natural Woman,’ she can move me to tears,” he said, adding, “It captures the fullness of the American experience, the view from the bottom as well as the top, the good and the bad, and the possibility of synthesis, reconciliation, transcendence.”