Got to love the chutzpah in the hypocritical disparity between the content and other behaviour of Metallica and their ilk.
RAWK THE SYSTEM!!!!! Apart from that bit of the system which pays for my flash car, that bit of the system is just fine. BUT RAWK THE REST OF THE SYSTEM! Just to be clear, if you rock the bits of the syetm we like, we'll be sending the big boys round in their fancy suits, BUT RAWK EVERY OTHER PART OF THE SYSTEEEEEEEMMMMMMMM!!!!!!!
I'm going to do something that 10 year old me would absolutely hate and defend Metallica... a little.
While it's true that they definitely did grow thanks to tape trading, Napster wasn't just a bunch of tape traders. They were trying to turn tape trading into an actual business that makes money. It would be sort of like if a record store decided that instead of selling CDs, they were just going to sell tape machines and CD-R drives and have half the store be open for people to trade CDs around. Furthermore, Metallica didn't just get angry that people were trading their old songs around. They found out about Napster because new songs they were writing were starting to circulate through it and wind up on the radio. It's sort of like if you were halfway through writing and editing a book, and then suddenly your second draft shows up on Amazon Kindle Unlimited.
T-Series and Metallica weren't doing the same things back in the 80s, either. Metallica was giving away their own songs as a way to gain publicity, sort of like the music equivalent of shareware. T-Series was just outright selling you other people's songs. There's a huge gulf between noncommercial sharing - especially if encouraged by the creator - and commercial bootlegging. The former is more or less just collectors throwing files at one another. They don't really harm the market, they were going to buy it anyway and filesharing is just a hobby. The latter, the bootleggers, are actually harming the market by trying to compete with the original creators of a work. 80s T-Series looks a lot more like Napster than 80s Metallica, IMO.