My ole HJ75 ( 1985 ) has an interior light dimmer.
It appears Toyota located the switches based on the installers mood and day of the week.
AFAIK ,all vehicles sold in australia have this ,so Im assuming it is a requirement under the A.S.
All the vehicles I have owned since the 70s have a had a dimmer switch for the dash lights.
I think other Toyotas here use the same switch.
I like to dim it down on dark nights on long drives as its easier on the eyes.