You're kidding right? Unless you're an extreme audiophile with really expensive hardware, there really isn't a heck of a lot of difference between a CrO2 or Metal tape, which is what I always used back in the day. While the tapes weren't free, they also weren't ridiculously expensive. I agree that digital distribution has made it easier to copy stuff, I don't really think the penalties assigned to this kind of thing have any relationship to any sense of justice or reality.
The ever expanding copyright term has made many people, myself included, not give a damn about copyright, especially for older works (those more than 30 years old) which should be in the public domain if only our congresscritters weren't so easily and cheaply bribed by media companies.
As for the technical arguments about quality — I will concede most of your points. Tapes (whether reel-to-real, or Cassette) of studio masters could be as good or better than vinyl records. Most people couldn't distinguish between new vinyl records and tapes made from those records, using the best media, and high-end equipment. However, most home copies weren't on the best equipment, nor were they on the best tape media. Nor, would people make hundreds, or thousands of copies to give away to strangers. Inexpensive as the tapes were, they still cost too much for that. Home copying wasn't nearly the threat to the industry that digital piracy is today.
There was commercial piracy “back in the day” — but, those pirates had a much harder time than do today's. They needed to physically copy the records, print cover art, and (most difficult of all) establish distribution channels. They couldn't afford to give away their product — they had to find a profit somewhere between their fixed and variable costs, and the price of legitimate recordings. That put a lot of limits on the damage those pirates of yore could do to the industry. Today's pirates have world-wide distribution channels (the Internet), and near-zero variable costs. Piracy today is an existential threat to the music industry — and, more importantly, to musicians. (As I said in an earlier post, the middlemen of the music industry will be eliminated by legitimate means, through the process of disintermediation. That's not a loss — that's just progress.)