No - literally false.
I have watched people cry and puke in pain for hours at Vanderbilt ER - more than once.
I watched people die in the waiting area in a Huntsville, AL ER.
I also picked up a girl that was in massive pain from what may have been an STD - but had no insurance in Huntsville - once they ran tests and determined what she had they told her, and then later they closed the hospital floor. completely - no one there - no would would tell her what was going on - I would not believe it if I had not gone there and seen it.
I know people that went to ER and given a quick surgery and colostomy bag because that would stop the life threatening issue - and I know others who went to same hospital, same situation and left - then went to a different hospital ER and were treated with meds for days in hospital and left fine without the colostomy bag and surgery that the other was going to do (as it would be minimum required by law for life threatening issue / it would save them money since they had no insurance)
The law does not magically make 1,000- doctors show up and take care of problems at 3am at the ER either.
I invite you to visit the ER's in our small city and take note of the dozens of people each day and night that do not get care.
You could die from a tooth infection, but they can and will send you home with a recommendation for tylenol and follow up with a primary care person - since you have no insurance.
I've seen these types of things happen to lots of people over and over again for many years.
You can sit with your belief that a law was made and so everything it awesome - but trust me these things are happening every single day.
Even if you have money to pay for testing and scans, and someone to do surgeries - it's going to be quite the endeavor to get pricing and even schedule these things (with cash) without a doctor and getting a doc without insurance is fun too.
These places use all kinds of tricks to make it really hard to get help if you don't have insurance paying for it all.
Depending on which hospital you go to and how full they are, your insurance type or non-insurance absolutely will put you in a position of being sent away or not taken care of while others are.
There are times when they have people on staff that can do some things and they may amputate rather than try to heal as well - checks off the box for life-threatening - you got care... I have a former coworker who got two leg amputations over 6 months - rather than get care that would of avoided it.
So no, I've seen very many people that do not get 'literally all places do that' - and I'm talking about American born, English speaking folks.
I don't know how things are at your local hospitals, maybe you could find some folks who have had no insurance and see the interesting navigation of health issues there.