I would think that older people know...
When I was really young I played at recital competitions (clarinet) and my sister played piano in the same (she was good).
In these cases the audience always considerably outnumbered the players.
Later on when I was 10, or so, I played guitar with a local Blue Grass band @ local "coffee houses" and none of the instruments/vocals were amplified (including bass guitar).
Once again the audience greatly outnumbered the band members.
Added to this are the numerous band/classical local performances I recall from my youth.
Much later on, but long before "unplugged" became a thing, I also listened to various acoustic/non-amplied performances in the greater Los Angeles area.
In the late 70's I was waiting for a dinner table @ a local restaurant and Herbie Hancock played a few improvisational pieces on an upright piano they had available (he was also waiting for a table:-).
Never cared for his electronic keyboard stuff up to that time, but he was awesome on the acoustic piano, just doodling away.
Anyway, musicians often have audiences that HAVE experienced non-amplified music/sound.
DeKay