That's definitely not the case, because they have to know in order to bill you. To get us back on the same page, let's rescope and consider only elective procedures and primary care.
Your example is extraordinary and could be specifically excluded. Even if I got a treatment plan with equivocating language about "risk of procedures / changes / infections / etc" and all that noise at least I could make an informed decision about which treatment plan I think is appropriate.
The guff I was sold when we were shoved to high deductible plans a ~decade or so ago was that we could make decisions about our healthcare. They come up with BS estimates or treatment calculators that are from the insurer and not the provider.