learning can at times be quite difficult. Why is it difficult? It challenges our world views, which can be a very scary thing, particularly for people whose world views have remained essentially unchanged for decades.

Learning is difficult because it needs effort which isn't immediately rewarded, not because it is scary. What worldviews are challenged if one learns painting, skiing, playing piano, calculus, group theory, Chinese, C++ ... ? From my experience, learning the worldview changing facts is usually among the easiest things, for their significance is easily recognised. Motivated cognition may lead one to reject the facts, but they have to be (and usually are) learned and remembered before rejection.

What is really difficult: learning a complicated skill which challenges nothing, inspires nothing, takes a long time to master and is useful, but difficult to be excellent at.