The thing that makes RPGs uniquely fun is that they allow us to express aspects of human nature we might not otherwise get to express.
So for a MMORPG to have full expressive potential, it's important for it to be designed to offer gameplay that reflects the most important human motivations.
That means MMORPG designers need to ask themselves: What are the most important human motivations?
Here are some questions game designers might ask themselves regarding combat content, and some suggested answers:
Q: Is a capability for destruction part of human nature?
Q: Is it an important aspect of human nature?
Q: Is it so fundamental that it deserves to be part of the design of a full MMORPG?
A: I would argue that yes, it probably is that important.
Q: Is destructiveness all there is to human nature?
A: No. There are also impulses toward preservation, toward creation, and toward perfection.
Q: Is destructiveness the most important human impulse?
A: Absolutely not. It's pretty basic, but that doesn't mean it is or should be treated as the primary quality of human existence.
Q: Why, then, should destruction be the key gameplay mechanic of MMORPGs?
Bad answers that can be discounted right off the bat are:
A. "Because it's fun."
That's an insufficient answer because it only tells us that you like destruction; it doesn't tell us anything about people in general.
B. "Because it's clearly the most popular kind of gameplay."
That's not a good answer because it's a tautology. People say they like destructive games because those are the kinds of games that developers currently offer... but developers offer destruction-based games because that's what people are currently playing. This tells us nothing about what games people would play if they could.
Mere popularity has never been a reliable indicator of intrinsic value. It's a clue about potential sales success, but it also blinds people to alternative sales opportunities. Chasing something just because it's currently popular has never been a successful long-term business strategy, particularly after someone else has already obtained the second-mover advantage.
So why do we need still more MMORPGs designed to put destructive gameplay above everything else?
Designers who think that preservation and creation and perfection don't deserve (at least) equal time have an obligation to explain why.