Put away emotion and rethink
In the USA, you can't just force an individual or an organization to do something unless national security or public safety is at risk. American's have every right to be as ignorant as they want to be.
To say security will not get better without government interaction is ignorant in itself. Security has gotten much better without government interaction. Corporations have also moved to be a lot more secure--again, without government interaction. Most companies want to become more secure faster, but the costs outweigh the risk in many cases. Don't forget the risk management aspect.
So if this is the case, why is IoT so insecure? Well, consider where many of these products are made, then ask yourself if these countries have an interest in secure IoT; as well as if they have something to gain if there are a great deal of IoT devices in western countries.
Another aspect is how new IoT is. Companies kick out IoT devices fast to make money and ignorant consumers rapidly purchase them so they can boss around Alexa and brag about it. Security is an after thought, and will be until consumers begin to demand it. A company has to compete with many others, adding security costs money--they can't sell a product which costs $20 more than competitor products.
The answer isn't government involvement. In fact, the last thing you should want is the government sticking their hands into my or anyone's business. Taxes are high enough.
The answer is educating consumers so secure products are what begin to sell, and becomes in demand. You know... this whole free enterprise thing.
It drives me crazy anytime people start expecting the government to step in and make changes. If you're intelligent enough... get up and make a difference yourself--else your taxes will increase and minimum wage will stay low. When is the last time you've asked a company for a more secure IoT device? Do you educate friends, family coworkers about the dangers and risk of IoT--in a manner they can understand? How does insecure IoT negatively affect their family?
Start educating people on the risks associated with IoT, and how it can negatively affect their family. Do this and you'll see people forcing change. Without additional taxes and/or politicians finding a way to corrupt it.