From Rolling Stone https://www.rollingstone.com/music/music-features/cassette-tape-comeback-walkman-1234606978/ Thanks to the Walkman! I'd also add that most cars back then had a tape deck and it was the preferred method of listening to albums in the car. These guys always miss the cool equipment used to listen to the music is also a factor, if the players were all crappy I doubt the resurgence would have legs.
I wonder what this new market trend will do to the prices of high quality tapes from the 90s and 80s. I'm a fan of TDK tapes from those eras, also love That's tapes.
I used to buy NOS tapes at the thrifts for .25 cents, now they want a few dollars if you can find them. Ebay prices have also gone way up for the good tapes. Luckily they made millions and I think there's still years of NOS stuff still buried in closets and warehouses.