I'm not Australian.

The far lower costs in Australia are not due to executive pay, it's due to basic efficiency. Americans are doing things in horrendously wasteful ways, because the system is set to act that way, and changing our system of government is too difficult due to political infighting. One of many examples in the article:

> These things are highly optimized that companies will try to do the scheduling so they’re doing two or three jobs on the same street or in the same suburb on the same day, so they don’t have to drive across town to do the second job. If there’s a delay of a couple of days, it’s because they’re trying to make sure that they’re going to do your neighbors at the same time they’re going to do yours. The thing that costs you money in contracting is what they call truck rolls. I believe in the US there’s something like five or six truck rolls per solar installation. In Australia, it’s as few as one or two.

See also the US healthcare system. Or residential building.