You like airship pirates because you are afraid of water

You big girl's blouse.

I've played many games, MMOs included, and I have noticed a serious case of aquaphobia going on.  This often culminates in an attempt to cash in on pirates, which while not as popular as they were some 5 years ago thanks to zombies are still marketable, but water is not included.  Unlike Sea Monkeys, those lovable instant life pets that graced every comic book ad page from 1960 to 1989, pirates apparently do not need water to flourish.  I accept that piracy can occur outside of a purely aquatic environment, such as in media piracy, but this unholy compromise of airship pirates is really just insulting to the sea dog in us all.

I have worked out two reasons why I think this might be the case:

1) Hard to program.  Once you put water into the equation you have to worry about items or potions for breathing underwater and the deleterious effects water has on paper, spell books, ferrous metals, and the human body.  You have to account for the pressure differential between air and water and how this affects combat and movement.  You have to consider the nature of aquatic life and how it is not just like living in air or on dry land.  Then you have to find a way to put a dungeon in it.  All of this requires a completely different point of view for developer and player.  The players, mostly terrestrial in nature, are ill-equipped for extended aquatic adventuring.  I get that.

2) People are afraid of water.  This seems counter-intuitive given how much time we spend at the beach, in swimming pools, and bathing.  Yet some of our most nightmarish fears are born from dark water.  Things all tentacles and teeth, alien to our air breathing mode of thinking, live in the water.
Sharks.  Big fucking sharks.  They live exclusively in water.
As obligate air breathers water presents a problem that air does not.  With air pirates we have the constant problem of staying up in the air, but at least we are breathing and not worrying about our full plate armor all the while.  With regular pirates riding on top of the waves we have that persistent threat of sinking into the nightmarish belly of mother ocean where the big teeth things live and our full plate armor becomes a complete liability.

Storm Shark is the coolest spell ever devised in the history of ever.

Consider this: nobody ever suggests that pteranodons are still flying about in the highest clouds of the sky and even if they were, who cares?  Not a threat.
But there is always somebody afraid that a kronosaur is still out there somewhere in the vast oceans and it is just waiting for you to be drunk and fishing to come up and eat your ass.

Ah, Shit, Ahhhh, Holy Shit...this shit never happens in the clouds, man.

We are terrified of this stuff.

Yeah, this guy is just the biggest pussy ever in the whole world.  Smell that?   That's sarcasm.

Also we think it is boring.  In every cool movie about treasure hunting or spies if there is a scuba diving scene there is going to be a shark fight.  Fulci had one in a zombie movie.  Despite the verifiable statistics, that most of the time you do not have to fight a shark when you go in the water, the ocean is so boring to everyone who is not Jacques Cousteau that we have to put a shark fight into it to keep the audience sitting in their seats.  Because we think it is boring we mock Aquaman and play airship pirates to allow us to have the pirate trope and avoid the ocean.  Then we take our week's vacation to go to the beach and sit beside it and eat grilled land animal flesh.

Yeah, see now you want Aquaman but he's not listening.

So that's my theory, anyway.