The reason you require licensing for insurance sales is because it's very difficult to track all of the individual instances of malfeasance. So, the answer to your question is, "I don't know."

But just because I don't have particular instances of harm, doesn't mean this isn't an problem. If you let anybody sell health insurance, you end up with con artists selling sham insurance, and by the time you track down the conman, real people are hurt. Sure you can fine the shysters, or maybe even put them in jail (but probably not), but in the meantime, families savings are wiped out to pay the medical bills, or worse, people get sick and die because they can't get treatment.