Imagine that one thousand years ago you had a rough idea of the most likely overall future trajectory of civilization. For example, that an industrial revolution was likely in the next few millenia. Even with that unusual knowledge, you would find it quite hard to take concrete actions back then to substantially change the course of future civilization. You might be able to mildly improve the chances for your family, or perhaps your nation. And even then most of your levers of influence would focus on improving events in the next few years or decades, not millenia in the future.