Just anecdotally, I can tell speaker tech has progressed slowly. Stepping in a car from 20 years ago sound... pretty good, actually.
IMO, half the issue with audio is that stereo systems used to be a kind of status symbol, and you used to see more tower speakers or big cabinets at friends' houses. We had good speakers 20 years ago and good speakers today, but sound bars aren't good.
They do sound pretty much ok for very discreet objects compared to tower speaker. I only occasionally rant when sound skip a beat because of WiFi or other smart-assery. (Nb: of course I never ever activated the smart assistant, I use them purely as speakers).
Lower spec speakers have become good enough, and DSP has improved to the point that tiny speakers can now output mediocre/acceptable sound. The effect of this is that the midrange market is kind of gone, replaced with neat but still worse products such as soundbars (for AV use) or even portable speakers instead of hi-fi systems.
On the high end, I think amplified multi-way speakers with active crossovers are much more common now thanks to advances in Class-D amplifiers.
The time and money cost of going further than that is not going to provide a sufficient return on investment except to a very small proportion of people.