She applies it. To herself. Just because you think you will be the happiest living normal live, doesn't mean you think everyone else should do it as well, because that is obviously the only way to live happily. You can think living your life on the edge is the best way to enjoy it, doesn't mean you think everyone should risk their life all the time.
Tell this to the people who are, for example, against same sex marriage. You'd think that they would be fine with just abstaining from marrying someone of their own gender, but that's never enough for them, is it? There are also a lot of people who say things like "I have no problem with the gays, I just don't like it when they shove it in my face." In the real world, people might say they believe in "Freedom", but they are biased towards freedoms that they see as beneficial to them and biased against freedoms they see as harmful to themselves. And so a lot of people believe that their own right to not be exposed to anything that's "gay" is more important than the right of LGBTQ+ people to exist in public without having to fear for their own safety.
She didn't explicitly say she hates lesbians though right? Maybe she just means what's not normal is only girls having existing in the world with no guys
Yeah, I'll agree there might be a concerning amount of homophobia hidden between the lines, but I feel like everyone needs to take a chill pill or something, maybe once she falls in love with the love interest, she realizes being gay is normal after all, who really knows the route this is taking?