Being a gay man in China, the greatest pressure doesn’t come from the fact that others might treat you differently (in daily life, most chinese people don’t care about your sexual orientation that much), but rather from the fact that your parents always expect you to get married and have children like a ‘normal’ person. For the longest time in modern China, when a gay man falls in love with another gay man, the biggest uncertainty lies in whether your significant other will eventually marry a woman. It doesn't matter whether he truly loves you or not, the pressure to get married and have children is so immense that most gay men in the past decades in China actually married women. They didn't feel like they had the choice. Thus as a gay man it's extremely normal for you to worry your boyfriend might eventually leave you and marry another woman, to worry he might choose to be "normal" after all. People might think that the younger brother's sudden fight with Qin Lang comes across as a bit petulant, that he is too spoiled and childish, but what he felt in that scene and his reaction are, in fact, among the more nuanced and delicate aspects of the series.
For the longest time in modern China, when a gay man falls in love with another gay man, the biggest uncertainty lies in whether your significant other will eventually marry a woman. It doesn't matter whether he truly loves you or not, the pressure to get married and have children is so immense that most gay men in the past decades in China actually married women. They didn't feel like they had the choice. Thus as a gay man it's extremely normal for you to worry your boyfriend might eventually leave you and marry another woman, to worry he might choose to be "normal" after all.
People might think that the younger brother's sudden fight with Qin Lang comes across as a bit petulant, that he is too spoiled and childish, but what he felt in that scene and his reaction are, in fact, among the more nuanced and delicate aspects of the series.