“How about you reading these – “Vayoel Moshe” and “Al HaGeuloh VeAl HaTmuroh”? “
Many, including me had their emunah (belief in HaShem) strengthened by the six day war victory. For them reading something that may weaken their emunah is probably prohibited.
Likewise for someone not ready to learn kabbalah because of insufficient Nigleh (the revealed) Torah knowledge, the same reason applies.