I briefly mentioned the possibility of a longer life for the ocean liner as transportation in the thread about a delayed jet age; I asked whether the delay of the start of the jet age (meaning no commercial jet air travel until a later time).
What could keep the ocean liner longer in service as a major (if not the main) transoceanic means of travel?
It is said that once jet airliners began to fly transatlantic in the late 1950s, it brought down airfares significantly so more people could travel (granted, flying was still expensive in the early jet airliner age, before the 747 made it possible to fly more people in one plane more cost effectively). Thus the jet plane is said to be the ocean liner killer. However even without the jet airliner, could the existing propliners (or even bigger flying boats, as once proposed) still have sounded the death knell, eventually, for the ship?
Could the ocean liner have evolved in terms of speed (ie, like the SS United States, or even proposals for bulbous submarine-looking streamlined ships) as well as evolved in terms of airliner-style class stratification (ie, have a budget "economy" class vs. premium classes, with relevant differences in service) to cover a wide range of travel budgets? Like the airlines have done in recent times, could ocean liner companies have gone to the nickel-and-dime (a la carte) pricing model, where the fare covered just the cabin and basic meals, and everything else cost extra?
What would "modern" ocean liners (post 1960s) have been like (other than Cunard's QE2)? Would there still be (much smaller) fleets, or would the ocean liner still evolve into a tiny niche experience? (IOTL, there is only one true ocean liner in existence today--Cunard's flagship Queen Mary 2, which replaced QE2 in 2008.)