The best vintage stuff certainly holds up. Decades ago, I found some speakers at a garage sale... Dynaco A25 something. Looked a bit crude. Hooked them up and... holy crap these sound good. Only later found out they're considered classics. I don't use them any more because decades of standing later caused the woofers to develop a voice coil rub, but these'll get fixed up by the right person some day and probably still used a century after they were manufactured.
Almost everything else has gotten better, or at least a lot cheaper and less trouble for comparable quality. But speakers haven't.
Speakers have gotten a lot better but at some point you’re fighting physics. If you want to move a lot of air, you need mass and volume. Most of our modern systems using a fairly similar formula to speakers from the 1960s, but we have better materials and amplifiers. For example, you can use a neodymium magnet but this isn’t really a revolution in speaker technology, it just means you can make a smaller/lighter speaker.
That said, speakers have gotten a lot better since the Dynaco A-25 came out. They cost $160 for a pair in 1969, or about $1,100 in 2020 by the CPI. You can buy a pretty damn good system for $1,100.
Almost everything else has gotten better, or at least a lot cheaper and less trouble for comparable quality. But speakers haven't.
Mind you a lot of that old stuff was crap too.