I have no problem listening to Black Sabbath, Led Zeppelin, Rush, Jethro Tull, Deep Purple, or whatever on my main system. Most of them are pretty well recorded. The Steven Wilson re-mix of Tull is pretty darn good.
Just listened to some Black Sabbath and found the mixing and recording more than sufficient to enjoy both the music and the system.
I've only found one recording (Glass Harp) that sounded so bad I had to turn it off.
Maybe my stuff isn't "good enough" by audiophile standards for it to bother me.
FWIW, I have eclectic taste in music. I listen to a lot more than 60's/70's hard rock.