As far as I can tell the message of the movie is "consumerism is bad because it's emasculating and feminizing, real liberation can be found in ruthless hierarchies of masculine violence"
The only person I know who likes it IRL also has a tendency to complain about the "pussification of modern men"
A modern day version of Fight Club is pretty much the Proud Boys. In Fight Club, there is a scene that the Narrator tells Marla that Fight Club is "a support group for men only". In the same way, Proud Boys present themselves as a support group for men. Both Fight Club and Proud Boys say that modern society is trying to make men become feminine. Both Fight Club and Proud Boys focus on doing performative masculinity. Both are private militias that engage in criminal operations. Both have the goal of establishing, reinforcing a male supremacist society.
Proud Boys try to beat up leftists and progressives at political events. It's even known that the police work with the Proud Boys, just like how the police are in Fight Club.
fight club is "a support group for men only"
Some people think that Fight Club is anticapitalism but I disagree. It's only anticapitalist to the extent that the Narrator believes that capitalism is feminizing men.
The film opens with the Narrator having insomnia. The narrator talks about how he believes that consumer products are controlling his life. He talks about the fashion of the people at his office. He talks about starbucks latte. He says that he stays up at night and buys furniture from catalogues. He calls this habit "nesting" which he attributes as feminine.
Then he finds the testicular cancer support group. The men in the group have had their testicles surgically removed. Their wives have divorced them for being infertile. One man named Bob grew feminine breasts because of a hormone imbalance. These are men that the Narrator perceives to have their masculinity stolen from them. The Narrator connects with them because he feels like he also has his masculinity taken from him. After attending the support group, his insomnia is cured and he sleeps perfectly.
Tyler and Narrator make the fight club and then the narrator stops attending the testicular cancer support group.
Later in the film, Marla runs into the Narrator on the street. She asks him why he hasn't been attending support groups. Narrator says that he's attending a new support group for men only, so he doesn't need to go to the old support groups. The Narrator is referring to Fight Club but can't tell that to Marla. This forms an indirect connection to the audience that Fight Club is a support group and that it replaces the function of the testicular cancer support group. For the narrator, Fight Club is a support group for men who have been feminized or had their masculinity taken from them.