It is interesting to test people at just one device.

I used my phone on a mount, and completed the test with my wife, children and myself - I was interested (though not surprised) what an outlier I was, as I am colour blind in various combinations, but though my wife scored 'bang in the middle' - it was interesting that wasn't common.

My kids were both to the left of the scale fwiw - I was further right than 98% of people.