In the same vein, when undergraduate Samuel Ong first threaded his eyebrows in 2016, his parents were initially unsupportive.
"They thought it represented an emasculation of the stereotypical male self, which often features a rugged rather than a neatly-groomed look," said the 22-year-old, who is a student at New York University.
But his parents soon came around as they noticed that stigma become less common in recent years. "They saw more men dressing immaculately and placing a bigger emphasis on personal grooming," said Mr Ong, who now threads his eyebrows every month. "Once the barrier on personal grooming gets broken down, it's easier to explore different options and threading eyebrows is one of them."
Similarly, Mr Nathaniel Tan, a father of two, thinks this acceptance of men threading their eyebrows comes with the world's changing values. "Our fathers didn't really do it. They were more concerned about putting food on the table. That's perhaps why some of my peers don't think it's right," he said. "But now, people are taking cues from what we see on television, from celebrities and even politicians."
Even though the 41-year-old has never threaded his eyebrows, he is certain he will be understanding and accepting if his son, who is now 10, does so in the future.
"Of course I'll still make sure that he's not doing it because of self-esteem issues," added Mr Tan, who is a pastor. "But I'll remind him that it won't affect his masculinity. For me, being a real man is about what you have on the inside. It's not something eyebrows can define."
Whether having neat eyebrows make a man look feminine or masculine depends largely on the look they hope to achieve too, said Associate Professor Elison Lim from the Nanyang Business School at Nanyang Technological University (NTU) who specialises in the beauty market.
"You can trim your brows and still look very masculine, or you can choose to go for a more androgynous look," she said. "Certain looks may attract more comments, but I think taking care of yourself now is quite well-accepted."
The general rule of thumb for men, though, is to simply neaten their brows instead of shaping them. Ms Vanitha Subramanian, 40, a beautician at a beauty parlour in Little India called Rhemas, said: "For men, threading is more to neaten their eyebrows rather than to create a defined shape, like we would do for women."