Although I was around during the Summer of Love, and have memories as a child hearing "The Age of Aquarius" playing on my mom's AM radio, I didn't understand the significance of it, and had no basis for gauging sonic quality, nor any expectations that it should somehow sound lifelike. But by the mid and late 1970s, hifi was hot, and department stores routinely devoted space. Some stuff was seriously expensive, like big Marantz receivers. And the sound? Usually too loud, with too much bass and treble, because the salesman (and it was always men) had tone controls maxed.
Some of the sound heard from parties, cars and on the street (boom boxes) was awful by today's standards with heavy clipping. It was only in the 1980s that an Alpine rep gave me my first demo of high-end auto sound. Until that time, I had never heard so much clear and powerful bass, let alone in a car. And today, the sound from college frat/sorority parties may still be too loud, but it's not distorted! Probably a big JBL or Sony BT speaker there. Even the personal concerts from people living on the streets is worlds better than it once was.
You could still get crap sound in the 2010s from computers (I'm thinking Thinkpad X200) and Bluetooth speakers. I thought the latter class of product suddenly started to deliver flattish frequency response in a short period of time, like one generation of JBL or Sony speaker would have bumpy frequency response, but the next generation would measure a lot better. I guess I was pretty satisfied by the time JBL's 3rd generation Charge arrived, because I mostly stopped buying the things at that point. More recently, I bought a very inexpensive novelty BT speaker, and wouldn't you know it, even there the presence of DSP was evident, and though the response wasn't flat, someone had deliberately shaped it. And for a product sold as an impulse-buy item, I thought it was remarkable.