I’ve noticed that my mother pronounces Nanjing as Nayzzhing. I’m not sure if this is another “Americanism”, or another facet of my mom’s bizarre use of the English language (she also says sandwiches “samerchez” and “Dunkin’s Donut”).

Their point isn’t entirely clear except to those who already have an ear for Mandarin, but the gist of it is that the J sounds are just not the same and we should all stop getting our undies in a knot about it.