I never said the HomePod will not sound "good" but there is no way it can compare to a high quality stereo. I, too, installed my share of car audio systems, because I was once in the high end stereo business. And, I still have a high end stereo system; over 25 years old now, and the darn things cost almost $10K back in 1990. No way a $350 AI speaker can touch it today -- or anyone's $10K system.
So, the HomePod will be what it is, and likely I will not want one, for reasons already expressed.