sir,
i think you may have been a little ill-advised here. i lived in Japan for three and a half years, and had several cars. one of them actually turned 10 years old on me, and i do not recall this inspection.
the JCI inspection, quite similar to the MOT, can be very intrusive. the findings on the JCI inspection are used to calculate your insurance premium.
when/if your vehicle is involved in an accident, if your car is less than road worthy this can have an effect on the settlement, even if the accident is not your fault.
the main reason vehicles find their way over here, is simple, the Japanese do not have room on their island to store automobiles that they no longer drive.
they used to mostly just scrap them and recycle the materials, then some entrepreneurial men started selling clips, which eventually evolved into exporting used vehicles.
the United Kingdom has more lenient restrictions on motor vehicles concerning road use,
therefore, an automobile that is less than road worthy to the Japanese has usually been far better maintained than cars half its age in Britain.