That is a myth. About half of the clinic and psych/therapist offices won't take anyone that doesn't have insurance, they won't even take cash. Most of who is left have no sliding fee. The few who do have a sliding fee are booked solid.
The local Rape Crisis Center? There is a 6 month or more long waiting list to see anyone. And that was after a very re-traumatizing intake where they gave me disturbing pamphlets about old men touching little boys. (Not what happened to me at all.) So, I'm on the waiting list, feeling guilty about it, because someone who was just raped would need the help, even so long delayed(!), more than me.
Medical assistance does not cover mental health in the US. If I break my arm, I can get it set for free. But, if I have cancer, I doubt that chemo would be covered. And mental health services? The US emptied the mental hospitals onto the streets back in the '80's, and hasn't changed tune since. The most severe eventually got re-institutionalized, and everyone else severe got shite.
I did find a non-profit place that can see me for a sliding fee. (Just $5, and I couldn't afford that , twice.) The let me talk to a student for a few weeks, who needs to videotape our sessions and have someone sit in "to observe" half the time. But, I'm told that shouldn't interfere with building a trust-relationship with this student/counselor. (Who, "by law" can not see me after he gets his degree.) So, I go, and trying to explain what I've been through to someone who doesn't have a clue... has kept me pretty much constantly triggered for the last month.
So, why isn't there any sort of Hippocratic oath for counselors and psychologists? Why are they allowed to do harm instead of helping with healing? Why does asking for help mean you have to be hurt all over again and again, by the very people who are supposed to help?