A very unusual thing happened at the weekend, an event so outlandish, so vanishingly rare, that even in these times of general chaos and disorder it deserves our attention: someone prominent joined the tiny cohort of people willing to publicly criticise Oprah. I’m not talking about an attack from the right. Donald Trump and his Maga cronies routinely go after Oprah Winfrey as (feel free to laugh) a lefty agitator. I’m talking about the actor Rosie O’Donnell, on Instagram, calling out America’s queen for showing up at the Jeff Bezos wedding.

Of course, criticising someone for throwing in their lot with Bezos shouldn’t be in the least controversial. The gross parade of wedding guests attending his marriage to Lauren Sánchez in Venice last weekend looked like a catwalk of shame. There was Leonardo DiCaprio, hiding his face with his hat (we still see you!), in the company of his positively geriatric 27-year-old girlfriend, Vittoria Ceretti. There were the Kardashians, not hiding their faces. There was Jared Kushner and Ivanka Trump. And there, accompanied by her lady-in-waiting, Gayle King, who walked several paces behind her as is proper, was Oprah Winfrey.

Why shouldn’t Oprah go to the wedding of Jeff Bezos and Lauren Sánchez? It’s a big splashy event that, given the chance, wouldn’t any of us have gone to as well? (Honestly? Probably.) Still, we hold Oprah to higher standards. It’s Oprah, for god sake, the woman we grew up adoring, who burst through so many ceilings, who Tina Fey correctly cast as a god-like figure in that episode of 30 Rock (where her character, Liz Lemon, took too many pills, got on a flight, and hallucinated that Oprah was sitting next to her in club class). In that scene, Fey did what we would all do if encountering Oprah while our inhibitions were lowered: she sniffed Oprah’s hair, told her she loved her and went on a deranged monologue that included the phrases “I eat emotionally” and “I saw your show about following your fear and it inspired me to wear shorts to work”.

And it’s not only love that staunches our criticism of Oprah. We also fear her. It has been the case for years now that the quickest and most effective way for a screen personality to curb press criticism is to launch a book group, guaranteeing that every hack touting a book – which is every hack in existence – nurtures a tiny flame of hope they will be chosen and whisked away from all this. Who among us has a bad word to say about Sarah Jessica Parker (hello!), or Reese Witherspoon (hi!), or the apex predator of celebrity book groups, the original and best, Oprah.

Likewise: who can forget the cautionary tale of what happened to Jonathan Franzen in 2001 when he expressed doubt that being selected for Oprah’s Book Club was the best thing ever to have happened to him? Granted, Franzen’s criticism was graceless. (He suggested Oprah’s picks were a bit low-brow.) But his broader point about TV consuming literary culture was given no credence whatsoever. This was a few years before James Frey’s makey-uppy memoir was exposed, and Oprah’s book club brand briefly damaged. Instead, Franzen was burned alive for his remarks, not least by Joyce Carol Oates, whose novel, We Were the Mulvaneys, was chosen by Oprah that season and who told me at the time: “Jonathan Franzen perceives the Oprah book readers as mainly women, and he would prefer a male readership.” Brutal.

Anyway, back to Rosie O’Donnell, an icon in her own right who is now living in Ireland after making good on her threat to leave the US if Trump was elected. “Is Oprah friends with Jeff Bezos,” she asked rhetorically on Instagram in the wake of the wedding. “Really? How is that possible? He treats his employees with disdain. By any metric he is not a nice man.”

That was it. Doesn’t look like much, but it was seismic given the general timorousness around Oprah. And this despite years of evidence that a woman who was once a trailblazer for good has drifted into murkier waters, from her promotion of shonky showbiz medic, Dr Oz, to her enabling of cranks like Jenny McCarthy, and the power of positive thinking pseudoscience of Rhonda Byrne, to showing up at the wedding of one of the world’s richest men, who begrudges his minimum wage workers their pee breaks.

Going back further, you can even take issue with the aspirational tone of Oprah’s original brand, the only sustained critique of which I’ve read is by Janice Peck, an academic at the University of Colorado, who wrote a book called The Age of Oprah in which she questioned whether the media titan’s dare-to-dream ethos was so apolitical as to skew heavily rightwing. Per Oprah’s narrative, said Peck, “she was poor and living in sackcloth someplace and then became Oprah Winfrey and everything in between and the whole historical context, all the conditions that made it possible for her to succeed, disappear. The American dream is based on that notion of: if you just put your mind to it.”

I understand this point, although I also think there’s room for dare-to-dream cheerleading alongside rigorous, data-supported policy platforms. But whichever way you see these things, the bottom line is we should be able to criticise Oprah, right? This should not be hard. And yet as I type this, now, I have a small knot of dread in my stomach. Oh, god. I’ve done the wrong thing, haven’t I. Oprah! I’m sorry! I didn’t mean it! I still love you! Please pick my next book for your book club!

• Emma Brockes is a Guardian columnist

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