I think I've probably come full circle. When I was a teen, I listened to the stuff I liked, early Zep, Allmans at the Fillmore, early Traffic, Tull (mostly pre-Aqualung), etc. Once I started to ascend the heights of 'audiophilia,' I learned there were 'audiophile approved' records which were played to demonstrate the 'accuracy' or 'realism' of a system, or just to make it sound good. Alot of these weren't that interesting, musically, or if they were, they got beaten to death as 'demo records' that were almost unavoidable. Fast forward the 40 plus years of which the OP speaks: I'm now listening to what I want, rather than what shows off the system best. If the music and sonics coincide, great. If the music is great, but the sound can be improved by finding a better pressing, I usually do. But, I can't say that 'hi-fi' circles have enlarged my exposure to new or different music.
Exploring new music (whether newly released, new to you, or old stuff that you were aware of, but didn't take time to assimilate fully) is a pretty personal journey. And my taste and preferences change, and change again. I respect highly skilled instrumentalists, or a gifted voice or production, but none of that moves me in a emotional way. There is some intangible aspect to this that goes beyond consummate musicianship or a well written composition. And what I find magical may not be something that moves someone else. Perhaps part of it is mood, too. But, having the ability to get beyond the confines of genre and a willingness to listen to virtually anything without regard to it fitting into the 'type' of music I think I like has opened doors. Right now, for example, I'm digging a band called Patto, which was only extant from around 1969-71. They are categorized as "progressive," but that term fails to capture what they sound like, particularly the second album, Hold Your Fire, which is an interesting mix of jazz, blues-y, a 'rock' singer and a guitarist who plays complex lead lines and 'fills' with the touch and sensiblity of a vibraphone player (which he also was). Obscure, sorta, and great fun. I only got there because I decided to dig deep into a particular catalog, and the band certainly wasn't one of the names you'd know in passing.
I can finish that album, and switch to an old Janos Starker mono record or listen to a track from the Outlaws or one of the Lynrd Skynrd albums and switch to Ellington, followed by Alice Cooper. I haven't made the jump to 78s, but there is so much wonderful music from those early recordings- and a whole other life pursuing them.