Insurers have to publish how they calculate rates and premiums. Every method and justification has to be approved by state regulators before they even enact them. It's one of the most transparent industries already.
This is an astute summary of the practical effect of transparency in consumer-facing markets.
The information is there, therefore it is transparent. It's sort of on you if you are unwilling take it as a second job and/or hire a suite of professionals to help you understand.
That's not the practical effect of transparency. It's the practical effect of living in a complicated world that must be modeled with math that most people don't know. It is on the populace to learn the math (many resources are available online), or fund people who can evaluate it on their behalf.
That is just changing the definition of transparency. Transparency means the information is readily available. The math isn't there to obfuscate the information, it is the information.
All of the laws passed by Congress as well as case laws arising from court proceedings are public. By your definition, our legal system is also very transparent. But that doesn't mean you don't need a lawyer just to navigate this voluminous corpus of information.