While I am sure that you understand these things much better than I, I am not unfamiliar with, and did a quick refresher on the pertinent laws and clauses.
Now, of course you are correct that the DCC says that states may not regulate products from other states differently than they regulate their own. A state may have requirements that are not needed by any other state, but those requirements must be applied to in state products as well. In other words, it prevents states from engaging in trade wars with each other.
So, absent any other law, states would not be able to prevent insurance products from crossing state lines, but, there is a law, the aforementioned McCarran-Ferguson Act.
This act followed quite a number of other legislative and court actions attempting to put some sort of regulations on insurance products, as, at the time, fire insurance was the big thing to be concerned about (health insurance barely existed), and some fire insurance companies were fly by nights, they’d take your money, but when a big fire hit an area, and lots of claims came due, they’d vanish, they didn’t have the reserve to pay out the claims they had, and there was no regulation to assure that they would have reserves to pay claims. They were interstate, so could not be regulated by the states, but they were not “commerce” so could not be regulated by congress under the commerce clause.
The McFA was a compromise, that allowed insurance products to be regulated. I don’t know that regulating at the state level is superior to the fed level, but they thought so at the time, and it’s what we have now.
Do you feel that the McFA violates the commerce clause, or that it is just an unwise law? Do you think it would be better to regulate insurance at the federal, rather than at the state level? I don’t see how it can be regulated at the state level, while being sold across state lines. If the insurance is sold out of another state, then you are not the constituents of the politicians that would be regulating or investigating complaints against it. I see that as a problem.
It does seem the only viable options are to regulate it at the state level, and allow the states to determine whether they will allow products from other states to be sold in their state, or regulate it at the fed level. This having it both ways thing will return us to the problems that the McFA was put in place to solve.