Are advances in technology making speakers better?

Technology HAS made speakers better. Today's modest bookshelf speakers are light years ahead of most bookies say of 40 years ago.  But the basic technology used most often (a flapping piece of paper driven by a magnetic motor) hasn't changed. However, as others note, the materials technology has changed a bunch. Neodymium magnets, stiffer but lighter materials, the knowledge of how to properly brace a speaker cabinet to eliminate coloring resonances using computer simulations, and yes, computer simulations that can drastically cut down on the number of prototypes needed to be built so that the designers can get it "right"
the first time.  

For instance, compare any speaker from 1982 that cost about $1200/pair with Andrew Jones' Sourcepoint 10 here in 2022 at $3600.  The relative value, allowing for inflation, is the same. 

But that doesn't mean you have to upgrade every 5 or 10 years. Buy what you can feel comfortable with, but then just enjoy it for at least 15 or even 20 years. 

The increments in sound quality increases are small but over 20 years they can add up. Or at the very least, make quality sound available at prices no one would have dreamed of back in 1982. 

The only reason to change is if you desire something else - a sonic signature change as it were.  If that is the real impetus behind your wanting to "change" then go for it and make yourself happy. Life is short. Listen all you can. 

@grislybutter ah yes. I keep my phones for at least 5 years before moving on, even though others may chuckle at me. The only reason to upgrade is when it can't run the apps you want or because the new versions of software simply aren't written well enough (too much bloat) to not require a new, screaming processor. 

As others note, when Andrew Jones or any other engineer sit down to design a speaker, the targeted size of that speaker, and the market they are shooting for of course limits what can be done. 

But I don't think MoFi would have been happy if Andrew had come up with a 24" concentric driver in a 250 lb. cabinet, even if he could have grabbed that lower octave.  At the end of the day they aren't a "boutique" manufacturer, but one that wants to sell a "reasonable" quantity of speakers to recoup their investment in Jones' salary, the tooling costs, setting up a factory, and make a little $$ in the process. 

I am concerned a bit about Steve Guttenberg's observation that maybe the new SP10 were on the "bright" side.  Did any of you hearing them think that? Of course set up might be the key. 

@mijostyn I did get to hear the large Advent at a small mom and pop stereo store near NC State in the late 1970s or early 1980s. All us poor students lusted after those and the ones from maybe Polk that looked like large coffins. We half expected the grills to open and Count Dracula to come out.

I have a old pair of vintage ADS L520 in my bedroom. When I turn out the lights, I can pretend they are the large Advent... :-)