Breana Newton, a legal coordinator in Princeton, N.J., who posts regularly about books on TikTok, was one of the people who responded to Ms. Blalock’s video. “I am going to show you bookshelf wealth,” Ms. Newton, 33, says in a video of her own. “Ready?”

She then gives viewers a brief tour of her home, showing books everywhere — on shelves, in overflow piles here and there, and strewed across the bed. Absent is the sense that the rooms have been staged, or that the books were bought with the consideration of how they would look on Instagram.

In an interview, Ms. Newton said that she worried trends like bookshelf wealth encourage overconsumption. This year, she added, she is trying not to buy any new books.

Another critic of the trend, Keila Tirado-Leist, said in a reaction video: “Who does it benefit to constantly have to name and qualify and attach wealth to any kind of style or home-décor aesthetic?”

Ms. Tirado-Leist, a lifestyle content creator in Madison, Wis., likened bookshelf wealth to “quiet luxury” and “stealth wealth,” styles that have recently made social media waves.

Still, she was understanding that what drives a home-décor trend like this one is a desire to create a home that feels, well, homey. In another video, she described the idea of layering — that is, slowly acquiring pieces and building up to a finished look, rather than trying to buy a bunch of things all at once in an effort to chase a trend.

“Styling a home takes time,” Ms. Tirado-Leist said.

Another TikTok user put it more bluntly in a response to Ms. Blalock’s video: “Bookshelf wealth does not mean you have books. It means you have built-ins.”