The issue, i believe, is that the goalkeeping position has fundamentally changed in the last 3/4 years with the invention of the sweeper keeper and its importance in modern day top level leagues and tactics. It will take years for keepers to cone through with the skills required. Its like asking Son to play centre back, he may do it with some accomplishment, however, it is not his natural position all way of playing.
Until keepers come through the academies and get taught how to properly play the sweeper keeper, and it becomes part of the nature, we're not gonna see a glut of amazing goalkeepers, anywhere in the world, there are always exceptions to the rules of which there are two in this league at Liverpool and Emirates Marketing Project.
You look at Hugos mistakes, and they generally all come from playing the sweeper keeper role, similarly, you look at the mistakes of many other goalkeepers, and they generally come from the sweeper keeper positions.