They just need to explain what the premiums would be if they hadn’t dropped the mandatory purchase.
Think of it like the story of the Three Little Pigs ...
The little pig with the house made of straw had his house blow away every week, only to have it rebuilt by the insurance company. The little pig with the house made of sticks had his house burn down every month, only to have it rebuilt by the insurance company.
The little pig with the house made of bricks never had a claim ... but his insurance premiums kept rising to cover the insurance company's losses on the other two houses.
So he finally said: "Screw this!" and canceled his policy.
So now the other two pigs have even HIGHER insurance premiums ... because they have to cover all the costs of rebuilding the two homes by themselves.