There are 2,620 passengers on the Queen Mary (19 decks) which I believe is quite low compared to most ships. Anyway my point is that it really makes no difference whether there are 2,620 (there won't be as they are limiting the number of passengers they accept) or whether there are sixty in a dining car. It only takes one Covid+ plus passenger to cough your way, shout germs your way etc. That's why Amtrak needs to continue some social distancing and why allowing coach passengers in the dining-car is not a good idea. Incidentally, Cunard passengers must be Covid tested prior to boarding, not so on Amtrak so your chance of infection on Amtrak is greater - especially in a dining-car.