Earlier quoted context omitted.
These sorts of things have been dealt with for centuries by Buddhists, it’s a fairly common effect when you start with Zazen. This is why taking one part of the practice and abandoning the rest (most specifically, an experienced teacher) isn’t a great idea for everyone. Most of the time all you need to hear is “just let whatever comes up during Zazen go, and return to the moment” but alas, if you don’t things can go…
I think you are ignoring the fact that people have different brains. Sure, persist through mild discomfort. But would you advise people who are hallucinating to do the same?
The stuff that comes up, including the hallucinations, are brought to the surface through your practice, but they are not caused by it. The only way to deal with them is with an experienced teacher, therapist or with self discipline (the latter i only include as seemingly this is what shakyamuni apparently did).
Everyone is different, I agree, but sitting with inexperienced people and expecting some enlightenment experience is definitely going to go wrong for you.