i feel like you're joking but to answer your question anyways cuz I'm a good samaritan, canon is official content published by the mangaka. This is fan-made thus not canon.
theilikepie is saying that the direction of the actual kaguya series is heading in the direction that this fan-made oneshot is depicting(with an iino and ishigami relationship). But of course, it's just a joke he's making. No way do we know what direction the canon series will go at this point.
Holy crap they made it feel like an actual chapter of the series. And the interpretation of Iino's family life was just so good, it really made me sad. Aka would be proud.