I do not work for the cruise lines, and the cruise lines might not be the lobbyist to the law makers, purely on behalf of their passengers.
I was trying to open my mind, from the literally stated context a legal "repeal" - as in all-or-none. I.E., The posters of such topics might have no problem with the provisions of law still being applied to the often mentioned ferry boats, or to smaller river boats? I believe that they might be open to mere amendments of the PVSA, that would neither ruin or inconvenience their trips.
I believe that too much is inferred by the mere title of laws, say by using a legal term, "passenger vessel" in the title. For example, a law could have the word "reduce" in the title, yet increase that very same thing that the "title" infers might be reduced (e.g., inflation?).
How many posts repeat the title of laws. They could title it the "Cruise Critic Act" if they wished.
The "1000 passengers" figure and the quoted term "covered passenger vessel" were actual excerpts from a bill/proposed U.S. law, (that would not apply to ALL passenger vessels).
If a provision of law (requirement or prohibition) does not apply to all passenger vessels (i.e., not "covered"), then there would be no need for 140+ countries to agree upon changing a definition of any or all passenger vessels.
And, the term "covered" is a kind of common adjectival term, having specific meaning when used in a section of law; we would not substitute some other internationally-defined term for the words used in our own national laws.
I am not a lawyer proposing any specific law, but I believe that making adjustments (with both winners and losers) might benefit the passengers of cruise ships.