Cars are an iconic part of western culture in a way that no other 'consumer durable' will ever get anywhere near to.
They star in films and TV programmes (Morse, The Sweeney, Only Fools & Horses, countless road movies, James Bond films, The Italian Job, Bullitt..... etc etc. almost to infinity!)
We invest them with human traits and many people buy cars to express something about themselves and their values (or a fantasy version of themselves and their values) to the world. Some people are almost as sensitive to criticism of their car as they are to criticism of their family or friends. (Some, more so.)
Read Tom Wolfe's.. "The Kandy-Kolored Tangerine-Flake Streamline Baby" or "The last American Hero is Junior Johnson" for some idea of just what the car means in the last 65 years of American (or even British) culture.
No-one ever lived in a "tar-paper hovel" but spent their entire wage on a state-of-the-art hifi to put out the front as a statement to the world of their very being!
Cars are culture, glamour, danger, triumph, love, hate, identity and transport. They have shaped our world and our landscape in a way that a hifi, a fridge or a television cannot. (Yes, Television has changed the world, but i'll bet no television ever changed your life as much as your first car!)
This is why a TV show about hifi will never work. Too few people care. Despite my interest in the subject, I don't want anyone to make such a show.
I have seen films where cameras have more recognition than a sound system. TV series where the furniture is more iconic (Frasier) and 'House' where his motorbike and guitar are far more memorable than his SOTA turntable.
When 'Good Morning Vietnam' was first shown, did anyone ever come out of the cinema talking about the cool Garrard 401s? Maybe one or two, but I would have been too embarassed. If I watch a movie or TV programme and gush about the cool cars there is at least some understanding of this from wife and daughters. (Especially daughters who like cool American cars.) If I gushed about any hifi in a movie, they'd have me sectioned!