The ranking methodology could be better, yes. But a very important criterion is citations, so that works. Another very important criterion is how good the professors are. With USA's infinite money, brain draining the best of the best is easier. Finding jobs after you finish is also another criterion. With just 5.5% unemployment, USA also holds an advantage. And Australia is practically begging scientists to come there. So Anglosaxon universities also hold an advantage there.
So, the way the ranking system works, Anglosaxon universities hold many advantages over other universities.