Yuja Wang. (Courtesy Yuja Wang)

Looking around the grounds of Wolf Trap on Friday night, I had thoughts about advocacy and the role of a critic. On the one hand, there was the musical story: Yuja Wang, one of today’s greatest pianists, playing not one but two concertos — Ravel’s Concerto in G and Gershwin’s “Rhapsody in Blue” — with her trademark mixture of ferocious dexterity and a light effortlessness that evokes the wings of a butterfly caressing the keys, while the young, energetic conductor Lionel Bringuier led the National Symphony Orchestra.

On the other hand, there were the rows and rows of empty seats. The people who were there, and there were quite a lot of them, screamed and yelled with whole-hearted appreciation. And there were plenty of younger faces among the picnickers on the lawn. But it was far from a capacity crowd. Fewer people than in the past view the chance to hear a star soloist, rising conductor and orchestra in popular repertoire on a warm summer night as a can’t-miss event.

Some people think it’s a critic’s job to try to sell the experience: Because I love music, I should let those of you who weren’t there know how much you missed. It’s true that you missed a consummate professional at the top of her game — indeed, I’m intrigued that Wang doesn’t (evidently) have the star-power draw of a Lang Lang, since she has every bit of the ability. The amphitheater at Wolf Trap may not be conducive to the most nuanced performance, but she gave one nonetheless, lowering the tone to a limpid whisper for long stretches in the Ravel before swelling to stretches of sheer virtuosity that were too effortless, sleek and gentle to be described as fireworks: rather, a spray of diamonds on velvet. Bringuier, meanwhile, let the winds linger lasciviously, gleefully over every note, especially in the Gershwin, before moving on to a long, slow, loving, elegant, slightly soporific account of Mussorgsky’s “Pictures at an Exhibition.”

All of this is well and good, and if you were there, you had every reason to enjoy it. But I think it will take more than a visit to a perfectly good performance, or my exhortations about how great the experience is, to persuade you or anyone else to rush out and buy tickets. Let’s be honest: This kind of performance is fine but not exactly fare for connoisseurs — just a fun thing to do on a summer night, and it might not be everyone’s idea of fun.

I’ve written before that Wolf Trap represents a middlebrow pastime. Its director, Arvind Manocha, is making a bid to up the artistic ante by presenting Wang or the rising violinist Chad Hoopes, who will play a Tchaikovsky concerto on July 29, or the co-production of “The Firebird” featuring gigantic puppets by the team that brought you “War Horse.” I wonder, these days, if the people who are interested in Wang and Hoopes are also more likely to be interested in slightly more challenging or offbeat artistic fare — if the audience that flocks to see orchestras play video game music might be more drawn by Beethoven and Brahms or John Adams and Jonny Greenwood. I realize, however, that programmers all over the country are asking themselves similar questions and tinkering with their formulas to find out what might interest the public — apart from an offering like the NSO program the night after the Wang event: a performance of John Williams’s score to a screening of “Raiders of the Lost Ark,” which was announced in advance as sold out.