Healthcare is such an asymmetric market that there will never be enough information for patients to price things accurately.
It's like if every road we drove on had a different toll every time we travelled on it, and we didn't quite know what the total would be (or what construction projects you might encounter along the way) at the end.
It's made worse by the high value people put on their health and their low knowledge of healthcare in general.
I worked in a hospital for 13 years, most of it on the billing and medical records systems. There was a single project I recall that tried to do price estimation for patients up front. It worked best for lab draws because a fixed number of vials were drawn for a finite number of predetermined tests. Anything beyond that involved human judgement at the time of service:
A doctor decides which X-ray views they want taken after seeing an injury, and may need to order more after the first results, and the radiology tech has some leeway in how they actually perform the imaging. A choice between X-ray, CT-scan, and MRI is pretty much an order of magnitude difference in costs between each, and determining whether an injury is bone, soft tissue, organs, etc. may require any or all of them.
Surgery is wildly unpriceable. The number of shots of anesthesia will differ for weight, metabolism, actual length of a procedure, and individual reactiveness to the medication, and the anesthesiologist may need additional medications to stabilize a patient's vitals. Each surgeon is making similar decisions as they go along; all of it has a cost and some tools/medicines are pretty expensive but no good surgeon will have price in mind during surgery; they'll use the best available method.
The article wants to blame insurance companies for price variation but that's a bit of a red herring. Every clinic and hospital does different numbers of various procedures and has different patient demographics so outcomes and severity will vary. ERs and cancer treatment are notorious cost-centers, whereas radiology services and outpatient procedures are the money makers.
Hospitals and clinics have no choice but to pick and choose a set of services each year to raise or drop the prices for even before negotiating with insurance companies on actual reimbursement. Medicare and Medicaid also reimburse at (even lower) fixed rates so hospitals are always balancing costs for the number of commercially insured patients against government insured patients. Hospitals can't refuse emergency service to anyone, so they're also forced to eat the costs if they don't play the pricing game to cover ER and subsequent treatment costs.
The whole thing is a terrible mess and socialized healthcare is the solution.