I think complexity and cost are what makes it taboo.
Try spending some time at r/budgetaudiophile and learn how real people live their lives. They want decent audio, but many have very tight entertainment budgets. Right now we are in a GREAT age of budget speakers, where some really amazing boxes can be bought for less than a layperson's paycheck.
TV's aren't bad either. $500 gets you a LOT of television screen area now, even if it doesn't get you the best whiz-bang picture.
Blu-ray players? Cheap as cheap, and >90% of the people would be happy with whatever you can buy at Target, as long as it lasts a few years. Same with streamers, where $50 plus a subscription or two goes a long way.
So where is the roadblock to affordable hi-fi that could get our children and grandchildren interested? Oh! Well suddenly I read these pages and hear about how the latest 13.4.4.2.6.8 receiver
"only" costs $3299. That's all? I'll take two!
Dolby's nonstop adding channels and surround modes, with the correlating increases in complexity and price, tend to push people away. A LOT of people were and still are happy with just 5.1. There's such a thing as stress caused by knowing "something better" is out there but you can't afford it (see people who trade in their low mileage cars every 3 years). Buying more and more speakers, needing more and more space, running more and more wires, justifying it harder and harder to the wife... yeah forget that noise. Joe Blow winds up dropping $250 on a soundbar or foregoes even that and listens to the TV speakers.
Hint: If you price equipment into a place that only boomers can afford it... only boomers will buy it.
I'm in absolute love with my Marantz NR1200 and I wish more manufacturers would take a chance with a basic 2-channel AVR so prices could come down more. Take out all the surround modes, all the DSP effects, and just downmix to 2 channels and call it a day. Many people would be content with a quality 2.0 or 2.1 movie experience if it fits their budget. With housing crunch as it is, a lot of people don't have spacious living rooms (or a living room at all) to set up an extravagant system. Just don't drown the consumer with such a plethora of choices.