Supergirl: Okay, but why they are just friends?

The question they should ask at interviews is not if Kara and Lena are friends or not, but why they need to be just friends.
“Well, because Kara is straight.”
And then: Why she’s straight?
The thing is that at the end of the day, Supergirl being straight is a decision. The people behind this tv show made this decision. And if you put this vs. the reality of lack of LGBT+ representation, one more question arises: Why this decision has been made?
This answer is simple: It’s because they chose to privilege straight people over gay people. It’s also because they see Supergirl being gay as having some negative effect on the show or the fact that Kara being bisexual/pansexual would make her different somehow.
You preach “love is love” and “everybody is equal,” but at the end of the day, Supergirl is still straight.

The truth is that being gay is perceived as bad or inappropriate, and we’re not treated the same at all. But recognizing this isn’t a bad thing. On the contrary, it’s the first step to do something about it.
This unwillingness to recognize problems is why I tend to be careful with shows that say “we are supportive” while completely ignoring one girl as a valid lover for another girl. But I’m digressing.
All of this, of course, isn’t just about Supergirl. It’s about each character that writers decide to make straight while we live in this context of inequality and bad LGBT+ representation. And even the fact that questioning this feels too much is a proof of how LGBT+ narratives aren’t treated the same.
Think about all blockbusters with only straight people without any effort.

But we understand that this is a process, that there are more than what a writer wants influencing the decision, and we can’t eliminate every tv show that does this because we wouldn’t watch anything. But then, when an opportunity appears which is what’s happening to Supergirl, where they already have a perfect (and loved by LGBT+ people) couple ready to go, the question remains: Why not?