Surprised a 30 year old cassette is still playable without falling apart. Maybe I should try some of mine.

They are surprisingly durable. I have a tape I made in 1990, it's followed me across continents and been in cardboard boxes, basements and attics. It still plays flawlessly.

Not wanting to push my luck, I archived it. On Minidisc.

I have quite a large CD collection. Two albums from the same era are unplayable due to oxidization, same band Banco De Gaia, pressed at the same plant in the UK too.

Yep, but the tape often "overspeaks" with the next winding, so you can already hear what comes in the next 2 seconds. :-) Quite interesting effect.

There is a reason they are often used as archival medium.