No. Possibly Kishore Patil, who was born yesterday in Mumbai, will build a replacement for her on a whim when he is 70, using self-assembling nanobots, or possibly next century the Creative Cold War Re-Enactment Society will cosplay 20th-century steel-mill workers and welders long enough to build a replacement for her in a period-correct fashion, but nothing really resembling Cunard will exist in a future where building a replacement for her is possible.
Not to toss cold water in the face of your maudlin science-fictional musings (kidding I’m totally doing that), QM2 is the 51st largest passenger ship afloat.
They call them “cruise ships” now, because the only reason to float around like that is fun, not business. So they have waterslides and such. Slightly less old-growth hardwood paneling, fewer places where one is allowed to smoke cigars.
But no. There are ten Greeks who could build another Queen Mary as a lark, and that’s just counting Greeks. However rich you think the world is? It’s richer than that.
Zeppelins, though. Those, I will grant you, have gotten scarce. Oh, the humanity.