I think you two are speaking on different levels when it comes to purpose.
Zen I think is talking about purpose in game, whereas Naiba + OP is on a practical engineering standpoint.
Furthermore, Zen is places aesthetics above purpose, as apposed to Naiba, where purpose trumps aesthetics. Not that one is overtly more important than the other, only that more emphasis is placed on one but not the other.
I’m just stating this because this could go on for a long time without going anywhere. 
That said, it is important to note that in IB, as far as we know and as per the devs’ statements, realism rules except when it hampers good gameplay.
Star Citizen is unrealistic and laughably so from an engineering standpoint, which was briefly talked about above. However, it’s just a game, and has no effect on reality whatsoever. And who knows? Maybe in the future, the style of the ships will make perfect engineering sense because of this doo-dad technology or what-have-you gadget. The point is that this is a science fiction genre, and realism, along with aesthetics, is a highly subjective point just because it’s, well, fiction. Pure imagination.
However, when realism is stated in regards to sci-fi, it tends to carry with it the ideas and knowledge of today’s tech and theory applied to the future.
With that in mind, all that remains is to determine how much baggage we want to carry into our game.
So far, we have glorious 1:1 scale planets with realistic features, wind, proper planetary belts, REAL FLIPPIN NEWTONIAN PHYSICS (!!!), and with the last update, we have a pretty sweet drag system.
All of the above could have been short-cutted across to get to the core game play of IB. Small planets, ED style belts, and hard-codded per-ship flight models. Honestly, none of the fancy stuff we have now is actually needed for the style of gameplay that IB is planning to employ. But we have it, thank goodness, because of the mantra realism rules except when it hampers good gameplay. (and because we have a truly epic engine to play with.
)
We have the tools, why not make stuff with them?
Now, as a final note, I have absolutely no doubt that the current direction of the ship design is intentinal. Keith and Flavien aren’t wringing their hands screaming at Jan demanding what on earth is he thinking building tanky looking ships.
I’ll leave it up to you all to decided whether or not it’s realistic.
I personally am somewhat disappointed that we probably won’t get the KS concept stuff. Like the orange neon glowy Hellion/Helion
skin. Or the Hellion for that matter. But I trust the devs to push the game in the right direction.