I have to agree with you, but sometimes one must remember that in real life there's a mix of the two. But, i get what you're saying as this is just manga and caters to the specific genre. And i know i deserve to die, but i don't think i was the only one that slightly and secretly shipped the two brothers together(≧∀≦).
I haven't finished it yet. But I'd say it was pretty good. At fist I also had your thought. But well, I came here for a good story and a plot. Not for straights or gays. The author did a good job of showing different povs. I see character's growth, challenges, difficulties, emotional sentiments and characters. That's absolutely beautiful.
Just my opinion tho.
That's exactly what i wanted to say ╮( ̄▽ ̄)╭

As someone who is a shoujo and yaoi fan, I have to say I don't like it when they mix the two. I'm not sure if the author was trying to showcase the variety of sexual orientations in the fashion world or if they were just trying to get more readers by attracting yaoi fans but I'm glad they didn't really go through with it. Because let's be honest, if this was a yaoi manga, those brothers would be in some incestuous relationship and gay for each other or others or whatever. Everyone in a yaoi is basically gay, which is fine because that's what I'm reading it for. But when I read shoujo, I just want the shoujo. They're both unrealistic realities that can't really exist at the same time. Because everyone's straight in a shoujo and everyone's gay in a yaoi. If it was any other manga that wasn't basically a romance shoujo - sports, seinen, whatever, I would be all for shipping yaoi ships. But this is one of the few times when I'd rather not. Idk, just my opinion on the stance of "yaoi" fanservice in shoujos