I like the airship idea over ocean ships because land doesn't get in the way. I imagine a ring of airships encircling the globe based on the prevailing winds. Except bigger, like a handful of sky cities (hydrogen being abundant, the square-cube law being what it is).
So instead of shipping something from the other side of the planet, you can just wait a few weeks until the warehouse is overhead, and burn a lot less fuel overall.
Or maybe you're having a conference in one. Either take a plane there and have your conference in the sky, taking the slow way back. Or get on when it's overhead and take a plane back (or if you're really patient, take the long way around the planet). The change of scenery would be much better than just flying to Vegas all the time.
New York City to (near) London is almost certainly the most common route by ship and it really isn't that many people in the scheme of things. I couldn't imagine having gone to my boss and telling them I'd spend a week getting to London for an event and spend 4x or whatever the amount. You can also get New York to Hamburg or a shortish train trip from Paris. And business passengers are most of the (especially premium) travel volume on those general routes. (And that doesn't even take into account far less frequent liner schedules.)
I don't dispute that, if you take budgets out of the equation, we could probably make corporate events more exclusive and more fun, but that's not really the way things are.