That's generally true in the states, but it is even worse. You as the patient don't see the actual price before the procedure (unless you ask). After the work is done, you then get a statement saying how much the procedure cost, what your insurance paid and what you owe. All those numbers are opaque and negotiable. Even better, it is common for insurance and the provider to continue sending you bills for months after even common procedures like child birth. It's a total mess.
Yeah, mostly a hospital could tell you what they will probably charge but they don't have all the variables to come up with what the actual negotiated charge will be nor what your co-pay would be.
Oh and just wait until you get to the sleazy methodology for charging those rates. Childbirth for instance, the room will be billed to the Mother for the days before the birth. So the Mother probably meets their deductible, then as soon as the child is born the room and all the things in it get billed to the child who now has a new deductible to hit before the insurance company has to pay their full amount.
Costs in healthcare aren't very "real". US providers use what they call a charge master to determine prices. So while an "IV" may show up on the bill, it's not the actual IV you're purchasing when you're in the hospital. Behind that number the hospital has factored in all sorts of cost centers such as part of the nursing staff cost for example.
These "costs" therefore do not represent the true actual cost of providing the service, but rather the charge that the insurance company will pay. Insurance companies have a negotiated rate that they will then pay to the hospital. One of the major "hidden" problems in our current healthcare market is that there exists extreme consumer price insensitivity (since most cases are covered by some type of insurance) alongside large consolidation of healthcare providers.