In the fitnah filled modern times it is obligatory to have a Shaikh. My assessment. Those who want to ignore it do so at their own risk. Noble Qur'an told Companions (RA) that beloved Prophet (PBUH) cleanses you by reading the Verse of the Noble Qur'an. Tasawwuf is imitation of that. In India there is a book called Rapidax English Speaking Course. 20 million copies of that were sold decades ago. It is still selling and more books like that have appeared. Let us put the total combine number of such books at 100 million. Out of those 100 million buys I have not met even a single one who would assert that he speaks English because of that book or the books of that type. Ergo - you need a teacher to learn. Even in case of spirituality. This is ad hominem. Purpose of a Shaikh is to take you closer to Allah (SWT) and not the opposite. One should be very careful about choosing a Shaikh but your import, that you have repeated earlier too, is rather missionary. Your disposition is negative.