The reason fans of Supergirl think her character might be gay is that they’ve pieced together clues from previous episodes in order to come to such a huge conclusion. The friendship between Kara and Lena Luthor blossomed in Season 2 after the two were introduced for the first time. They became besties, and fans of the show started hoping something romantic would come of it.
One user on Twitter named @CloiSupercorp wrote, “Lena is the one who makes Kara happy & hopeful because Supergirl is gay and in love with Lena Luthor." That same user also posted, “Supergirl is gay with Lena, her best friend & love interest. They’re the perfect description of Clark’s wedding vows.”
In reality, it doesn’t look like Supergirl is actually gay in the show. For those who don’t know what queerbaiting is, it’s what show creators do in an attempt to gain attention from queer audiences by sending out vibes that a queer relationship might be incorporated in the show without ever following through on it. It’s looking like that’s exactly what’s happening here.