Being the flattest continent does not mean that the continent is flat. My point is that there is still plenty of hills and steep terrain around. It's not self evident that if you build a train line somewhere in Australia, that line will be flat. In fact the Pilbara automated rail network does contain some steep sections.

It still snows in Africa, and if you tried to climb Jebel Toubkal without a jacket I don't think knowing that Canada is snowier would provide you much comfort.