Well, I don't know that I've noticed "increasing number of Americans and Canadians are going to Class 8's. or Toterhomes". Maybe, maybe not. Are there hard numbers to back up these statements?
As was mentioned the attraction for these large semis is going to stay pretty small because of the impracticality of them. IMO anyway. What do you do with them when you aren't moving your trailer? Not exactly practical for day-to-day usage. Some will use them, but the numbers will stay small in the US anyway.
Suppose we can get over the Richard measuring now? What works in Australia will work to a limited degree here, and vice versa. That makes neither superior to the other overall, just better in their home market.
I'll have to admit I don't understand the need to prove that the Aussie trucks are better.