@Xaelath I said "not the only reason," not "it does not matter." Not to mention the fact that Watamote is not an idol franchise and the popularity of this manga in the yuri community has its own reasons. The fact is that Western culture has never suffered from an obsession with the innocence and purity of female characters, not to mention the illusions that Tsundere-chan can be your wife, lol. Therefore, Western fans don't understand the general picture of the attitude towards such franchises in Japan itself, thinking that all the problems relate exclusively to ships.
For example, when Bandori's producer was asked about this story, he said that he decided in the end not to add male characters to Bang Dream!, "because romance would complicate the story while I would prefer it to be just a story about the power of friendship and reaching a goal with friends". Plus, in his opinion, it’s much easier for you to sell an all-female franchise to both audiences, as women also love cute moe girls, while guys will look at cute moe boys as a threat for a number of reasons. In other words, it’s easier and better for you to sell the opportunity to more people than to give something objective to only a part of them. Well, unless you are not Nasu and you don't have money for FGO, which can offer both romance/waifu, and shipping without serious restrictions.