Don't see how ships to trade is a red herring. First Google result for "Black Death rats ships":
> The Black Death was also carried by rats on merchant ships through the trade routes of Europe. It struck Europe in 1347, when 12 ships docked at the Sicilian port of Messina. Subsequently called “death ships”, those on board were either dead or sick
Parent is using an example of a case where we know trade by ships helped cause the plague to spread, so is similar to how obese people have worse covid outcomes. No one is really going to go on a platform and attack trade by ships, though, just like in modern times no one is allowed to discriminate against the obese.
> The Black Death was also carried by rats on merchant ships through the trade routes of Europe. It struck Europe in 1347, when 12 ships docked at the Sicilian port of Messina. Subsequently called “death ships”, those on board were either dead or sick
Parent is using an example of a case where we know trade by ships helped cause the plague to spread, so is similar to how obese people have worse covid outcomes. No one is really going to go on a platform and attack trade by ships, though, just like in modern times no one is allowed to discriminate against the obese.