Those complaining about the dated US infrastructure needs to take into consideration the difference in land mass between the US, Japan, and South Korea. It's cheaper to update the infrastructure when you only have 1/100th the area to cover.
US 3,794,083 sq mi (9,826,675 sq km)
Japan 152,411 sq mi (394,744 sq km)
South Korea 37,911 sq mi (98,189 sq km)