Yes, that is true - you cannot crawl along everywhere "just in case"; in a railway analogy to this you have to trust the signalling system.
You are right that the QE2 was the last great vessel, though she is not the last liner - QM2 was built to full Atlantic liner specifications, although unfortunately she does look like a floating block of flats! At least she does not look totally awful like a lot of the modern builds do.