There is additional nuance here. Not all of the MRI machines are the same.

The USA typically uses machines with higher magnetic field strength, which are more expensive but produce higher spatial resolution. These machines are based on large superconducting solenoid magnets.

In Japan, there are many MRI machines with lower magnetic field, which makes them much more affordable while still quite useful. Some of such machines even use ordinary permanent magnets, which have much lower upkeep costs compared to the large superconducting devices.