Firstly, medical insurance should not be tied to employment. It is nonsensical that if you become too ill to work then you can’t afford to get better.
Secondly, the modern American medical schedule makes no sense to most laypersons, and even to the majority of providers because at its very base, built in the seventies, is the phrase “usual and customary”. Insurance companies have negotiated on a fractional multiple of this for many contracts that are now close to half a century old. Every time the fraction decreases from the insurance company side, the provider increases the fee schedule, and in the end the desired result on both sides is a small increase. This is invisible to patients until they have to pay some proportion of the rate as part of a percentage copay, fixed deductible, or all of it if they have no discount at all. Both are much more recent developments within the last two decades. Undoing this contractual tangle is financially risky to any hospital or provider, and the insurers know it.
Thirdly, there has been a proliferation of wonderful but expensive medical technologies that have a lot of patient demand without a solid understanding of the true long term benefit. Except for individuals that are so financially secure as to functionally be completely self insured, most patients are part of some sort of insurance cost sharing pool, whereby any one high cost patient reduces the funds available to the rest of the pool. The easy solution is to raise rates in the following year, thus driving out some lower risk individuals, and decreasing the pool size while increasing pool risk.