Tara Erraught, the young Irish mezzo-soprano, has been the darling of critics around the world — until a pack of them descended on her after her first essay in “Der Rosenkavalier” at Glyndebourne, criticizing her “intractable physique” and “dumpy” build.

The Old Guard – those white European males we love to hate – was certainly in evidence in the British reviews of Glyndebourne’s new “Der Rosenkavalier.” Five of them designated Tara Erraught’s Octavian as a problem with the show, more or less explicitly, based entirely on her looks. “Tara Erraught’s Octavian is a chubby bundle of puppy-fat,” wrote Andrew Clark in the Financial Times, adding, as an afterthought, “albeit gloriously sung” (evidently svelteness, not singing, is the point of the exercise?). In the Telegraph, Rupert Christiansen said that she “sings with vibrant assurance and proves herself a spirited comedian. But she is dumpy of stature…”

No critic should be too eager to cast stones. I have certainly written things in reviews that had people up in arms, and I have certainly observed that a given singer was not small, when the occasion warranted it. But there’ s a distinction between description and criticism. Mentioning a singer’s looks may be relevant in some cases, but dismissing a strong vocal performance as a “problem” because of those looks seems to me singularly clueless. Opera’s history has been full of the physiques that gave birth to the fat-lady cliche. To suddenly act as though credible looks represented the ultimate criterion of a successful performance is at the very least confusing, as if critics in the age of live broadcasts (“Der Rosenkavalier” will be streamed on the Telegraph website on June 8) had abruptly adopted a new set of standards.

It’s also a shade disingenuous, since I believe that if Erraught had been really fat, rather than simply curvy, the press would have held its collective tongue. We’ve learned enough not to call the fat lady “fat,” in her own hearing, but when she’s merely zaftig, it seems, she’s fair game. Furthermore, it’s lazy. It is perfectly legitimate to be underwhelmed by a singer; but there is an accompanying responsibility to think carefully about what was or wasn’t lacking in the performance, rather than kissing a singer off with faint praise (“gloriously sung,” if true, surely merits more than an offhand mention?) and blaming everything on her weight. (Not everyone, incidentally, saw problems. Fiona Maddocks of the Observer tweeted, “Ahead of full review: Tara Erraught’s Octavian is touching, innocent, beautifully sung, beautifully acted.”)

Opera remains the only entertainment field where these issues come up quite so regularly (remember the flap about Deborah Voigt and the little black dress?), because it’s the entertainment field with the largest number of larger body types. They do emerge in other media as well. One recent example was an episode of the TV sitcom “Louie” in which the comedian Louis C.K., a heavy-set, middle-aged man, meets a woman who seems perfect for him — except that she, too, is heavy. The female character calls him on his hypocrisy, talking openly about society’s double standard about “the fat girl” in a scene that represents a rare and welcome burst of public candor about  this topic. It’s especially refreshing because it focuses on the issues.

In opera, the discussion tends to revolve around movie-theater broadcasts of live performances, which are thought to stack the deck even more against larger body types, although the field is seeing the rise of some extremely talented full-bodied singers at the same time. In any case, as this recent crop of reviews demonstrates, thoughtful discussion on this topic in the media is not yet a given, though the considerable backlash on-line has already prompted some more considered responses.

It certainly brought wider attention to Tara Erraught, who, among other future engagements, will be singing the title role of “La Cenerentola” at the Washington National Opera in almost exactly one year. It would be a nice twist on “Cinderella” story if the story of badly-treated young woman who triumphs could actually come true.