for the same reason your people might choose not to concentrate on teaching shakespeare or the english civil war, these events might be central to your national history and story but they are peripheral to ours and not necessarily things we chose to focus on. in other words they are of greater importance to you than they are to us. how about you stop blaming europeans for why your countries are shit places to live? the chinese and koreans had a terrible time of it under japanese occupation but you don't see them letting their countries go to the dogs while doing nothing but whine about how evil the japs are.
First I come from the Europe so that I do not blame the Europeans for the situation in my country. And i learned Shekespeare but also Dostoyesky,Goethe,Viktor Hugo.. But if we are talking about Great Britain, do you really think that they have become dominant in the 17th, 18th, 19th. even in the 20.th century thanks to fishing and coal mines? I do not think so.