I love when the system actually works
I think this is probably one of the things the government can do that is unambiguously good and will touch the lives of many, many Americans. It's also an example of a market failure where there is no market for the product or service demanded. It's a textbook example of the tragedy of the commons where the gain on the TV signal is owned by no one and thus not protected. It seems like a perfect thing for the governing bodies of the country to spend time on if that's what it takes to get it done.
I do not buy your theory that this is pandering for votes. I doubt very many people will chose their elected representatives based on this issue. Instead, I think that is just a convenient rhetorical device by which you are discounting the value of this measure.
> Going further, what's the positive national interest in encouraging Americans to watch yet more broadcast television?
Personally I don't think it's in the national interest for the government to decide for its citizens what they ought to be doing with their time. Instead, it should observe what the citizens wish to do and, where appropriate and efficient, facilitate those activities.
I can buy that it's an example of market failure, but I'm not sure about the second part. According to the idealized free-market theory, this sort of stuff should be taken care of by the market just fine, by people changing the channel away from the objectionable ones, thus commercially penalizing them to the point where running quieter ads becomes the right business decision. That doesn't appear to have happened, probably because while people dislike loud TV ads enough to write to the FCC, they don't dislike them enough to actually meaningfully change their TV-watching habits (so channels with quieter ads don't really gain a commercial advantage).
The products are very differentiated, and there are only a few companies providing the products. But the differentiation is really what matters in this case.
As much as everyone hates loud commercials, channels can't actually gain significant viewership by quieting them down--no one is going to watch a drama with quiet commercials when they really want to be watching the football game with loud commercials.
This means that there's no incentive for a channel to piss off their advertisers by doing this on their own.
This is what governments are for--mandating the socially optimal strategy when the dominant strategy is something else.
Calling this a "theory" is giving it more credit than is warranted. It's largely an experienced opinion and the only kind of falsification you can do on it is see if implementing parts of it cause society to implode.
Seems like the manufacturing side might also be a market failure--it's a feature that most/all consumers want but since the market is fiercely price-competitive no manufacturer wants to pay for it. Still, it seems like a feature that Sony/LG/etc could advertise and gain a small amount of market share for.
It's not clear to me what evidence you'd use to show that this was unambiguously good, given that Americans have had the option to buy TVs with this feature for a long time, and mostly don't bother. To me, this would suggest that the assertion that it's an unambiguous good is at least questionable: if it's not worth a few extra dollars, how do we measure "good"?
There's no free rider element here, so I fail to see how this is a textbook case. The temperature at most public places isn't regulated by the government. Is it a tragedy that it's typically colder at the movie theater? No, experience tells you to dress a bit warmer. As with clothing and climate control systems, TV technology gives us the means to control our own environment: volume controls, DVRs that skip commercials, auto-leveling features, etc.
Given how much we can control/regulate our own personal environments, and even to some extent in the marketplace by having merchants cater to our preferences, do we really need this legislation and is it a priority given the current state of affairs?