Originally, the point of seafaring was carrying cargo. I won't get into the whole economics of historical shipping mostly because the topic, interesting as it may be, has been completely sullied by association with Krugman. Unfortunately P Krugman.
Be that as it may, in the Age of Sail cargo capacity was the point, and speed of travel a minor consideration. People were more than willing to put up with a longer journey if that longer journey meant they could carry more stuff.
Everything changed by the arival of steel, and in the 50s ship hulls were pretty much straight. Growing up in a Warsaw Pact country I certainly enjoyed the endless 50s, stretching on between 1952 to about 1985 or so, and therefore "in my childhood" ships were the classical, WW2 German design. Panzerschiffe, Graf Spee, that sorta thing. By then speed of travel became rather important, given that an inability to navigate out of danger meant sinkage. Cargo space conversely wasn't as much of a consideration anymore, due the to inexpesive abundance of steeli making ships overabundant in the first place.
Nowadays, cargo is hardly a consideration at all, due to the complete separation of haulage from any other activity. Modern shipping exists primarily to offer a floating platform to human interests (which mostly consist in launching planes to sink other people's interests) and so modern boats look pretty much like an implementation of "what's the absolute minimum waterstuff I need to get this sunbathing platform afloat ?". People certainly don't have the patience to wait even one single minute longer, no matter what infinity percent more haulage that extra minute would allow.
In short, there's six centuries' worth of evolution from the days when scarcity forced people to focus on the outside world to the days when abundance leaves people with nothing else to look at than themselves.
PS. This is the first time I've drawn anything in twenty years. Be gentle.———
- You may not think so, but if you look at what ship amortisation per ton-mile cost in gold in 1750 and compare that with the per ton-mile amortisation (also in gold) in 1950 you may be a little shocked at the order of magnitude difference. [↩]