I honestly don’t think we need a government solution to this issue. Consumers who want this security can buy from manufacturers with a reputation at stake such as Amazon or Apple. I don’t want your “help”. Let the market sort it out.
Consider food or automobile security: Should consumers somehow evaluate them? Check the wiring? Find out, at every restaurant and grocery, how long the food has been stored and where?
IoT security has another issue: It can affect others more than the end user. If my IoT is DDoSing you, what will the market do about it?