“It takes a lot of guts to face HDTV without makeup,” Ms. Brown said of Ms. Keys. “But I get it. It’s all fine. Choose who you want to be. Personally, I like to have a little concealer. But obviously it’s more than about makeup. I don’t think people understand how difficult it is for women like Alicia Keys to worry about the way you look every second. It is the ugly internet we live in. Let’s be nice to people, and not be so judgey.”

There is a sense you just can’t win. When Kim Novak appeared on the Academy Awards in 2014, there was much snark regarding her clearly augmented face. Laura Lippman, the crime novelist who was then 55, was appalled: Who were these internet trolls who would weigh in so viciously on an 81-year-old’s appearance? In solidarity with Ms. Novak, she posted a selfie of her face “as is” and invited others to do the same. It was a different sort of #nomakeup moment. “Damned if you do, damned if you don’t, is how I felt,” she said. The response, she said, was overwhelming: thousands of “as is” photos from all sorts of people, including one man, she said, who photographed himself on a hospital gurney the day he had a minor heart attack.

It’s just complicated, said Sheila Bridges, the interior designer. Given an alopecia diagnosis years ago, she decided to shave her head rather than contend with wigs or weaves, a private act that has subjected her to constant, uninvited public commentary. Also, people have been moved to pat her head. “Historically, beauty has been our currency as women,” Ms. Bridges said, “and when you do something that is inconsistent with societal norms, people get upset. It reminds me of when Gabby Douglas won her gold medals at the London Olympics.”

It was 2012, and the 16-year-old was taking home two gold medals for her performances, but much of the conversation around that historic event — Ms. Douglas was the first African-American woman to earn the Olympic all-around title — was about how her hair was pulled into a ponytail and secured with clips. “There was a tremendous backlash,” Ms. Bridges recalled, “and all these terrible tweets, and what was so disturbing for me was that the majority seemed to come from other black women. I’m like: ‘Are you kidding? She’s one of the world’s best athletes, and we’re talking about her hair?’”

Gail O’Neill, a journalist and former model, said that for some, Ms. Keys has become a Rorschach test, and the disapprobation for the singer’s personal choice comes from women who are measuring themselves against it. “When women start applying makeup as preteenagers,” she said, “by adulthood, that mindless habit can result in a mask we don’t even know we’re wearing until someone like Alicia decides to remove hers in public.”