There is a difference between the ascetic seeking out painful, tortuous practices and sitting through pain. Seeking pain is indulgence in pain, thinking the pain will bring about spiritual progress. Sitting through pain is transcending the pain to focus on what is really important: what is suffering... cause... cessation... path...
I have never been to a Goenka retreat, but I see nothing to suggest the method involves indulgence in pain.
As for the "hypnotic" criticism, I have noticed that many Buddhist practices do seem geared toward a type of "brainwashing" by getting the person into a calm place of trust and then planting the dhamma deep inside a person's consciousness. However, this is not an evil thing. Our suffering comes from a deep seated ignorance and clinging, and the only way to eliminate suffering is to dig deep and replace greed, hate, and delusion with virtue, concentration, and wisdom. What is wrong with that? Why else sign up for a 10 day retreat? Of course, before and after the retreat, I think it's important to reflect on how such training affects a person, and to decide to move forward or try another practice.
Sotthī hontu nirantaraṃ - May you forever be well.