Interesting. I'll check out the video! One of the most important parts for me was that I really wanted the end to sound like me, the writer, talking to you, which is why it's so direct. The fish, to me, are representations of the people around me and what I see in the world. While I do agree that preachy writing can take me out of experiences, I didn't want to risk losing the "me" in it.
To me, I'm imposing my belief onto the players as much as I would be if I was talking to the player in real life, just because it's coming out of a sock-puppet fish doesn't mean that it's not coming from me, and it shouldn't be treated as an absolute truth.
However, I think this genre is the only way I could pull off something like that, and even so, I agree that it could've been done a bit better.