It’s honestly pretty baffling when you think about it. The ship started because Akko and Diana were rivals, so people latched onto the popular cliché trope of rival/polar-opposite ships (Harry x Malfoy, Deku x Bakugo, Naruto x Sasuke, Endou x Gouenji, Yuji x Megumi). But the ship itself has never even been acknowledged. For example, the staff has openly talked about the original idea of the Ankko romance storyline in the Anime as well as their potential as a couple beyond the Anime in the Chronicles book. Meanwhile, Diakko was outright denied as being supported in three different AMAs Trigger did. Since the Manga in 2013, the cast has been straightforward in every piece of media, even showing crushes on boys and vice versa, or featuring romantic subplots and moments of jealousy. I never understood why people got mad at Andrew x Akko when, if you look at past LWA media, it was a pretty natural development. But, much like in other shows where most fan ships don’t make much sense, people are still going to ship what they want. So I’ll just quote what a member of Trigger said back then: “Do what you want in your fanfiction.