Did the Old Receivers Sound Good?

My first system purchased in 1973 was a Pioneer SX828 with Large Advent speakers, an Advent cassette deck, a Thorens TD160 turn table, and a  Sure V15 Cartridge.  The Pioneer, putting out 54 watts into 8 Ohms, is currently driving DCM Time Windows in a second home condo in Vermont.  The DCMs from my 80s system.  The source is a BlueSound Node.  
Overall character of a classic receiver is smooth and sweet as chocolate pudding that many people like and that is forgiving of poorly engineered recordings but presents an opaque picture of reality unlike modern electronics  that are as clear as a Riedel wine glass in the right system.  Dynamics are acceptable but far from the micro dynamic and macro dynamic resolution produced by today’s equipment.  Resolution in general is characterized by absence thereof.  Images are distinct but without the air that is present between images that presents the three dimensional, dense, and palpable images of today’s equipment.   Timbre makes instruments recognizable but that’s about it.  The tuners are able to pull in the signal well in metro areas and sound as acceptable as FM can sound. That said, they produce very nice un-fatiguing sound four hours of background listening and that renters of my ski condo enjoy.  I also enjoy the nostalgic sound when there for background listening.  They are built for reliability if maintained by cleaning volume and balance controls and recapping the few caps they have as evidenced by my almost 50 year old unit.  In conclusion, they are far from todays standards, pretty to look at (oiled wood, blue and white lights glowing, satin finished metal), reliable, and excellent for background listening.   Some like them better than today’s equipment.  Appreciate them for what they are.   To each our own ears.   It amazes me how far technology in our hobby has evolved   

True. Electronics have come “a long way.” Todays electronics are wave soldered using micro component SMDs and SMD semiconductors, robotically positioned on the computer designed boards, from computer designed and modeled circuits. 
 

The old stuff was designed by hand, individual circuits using discrete components.
 

Yeah, we’ve come a long way. But not sonically.

There’s more to this than just the specs - I have a vintage system of Sansui AU-9500 with JBL L65 & Luxman TT at my summer place. It’s equal parts nostalgia/performance but it brings me just as enjoyable an experience as when I’m listening at home in my dedicated room. That vintage system fills the place with great music and good times. I can say emphatically that the vintage pairing of Sansui and JBL has a magical quality. Like a time machine for me... STILL sounds amazing and yes, all the vintage pieces have been upgraded and redone by a fabulous shop in Massachusetts that specializes in "better" vintage gear. So, maybe not better, but not worse - just different although equally enjoyable. Just my opinion.

You really can't compare the vintage receivers to modern receivers even if you put modern caps and resistors, it changes the original sound of the vintage receivers when this is done.

That could be another comparison. Put new old stock capacitors in an older piece of equipment and then have modern capacitors and other components installed in the same piece of gear or a second identical unit just to hear the difference.