Old Cabernet turns colourless?!

klezman shared some links said

A friend of mine posted a photo of a bottle of 1978 Gallo Cabernet he just received. It was colourless throughout, but with a ton of red sediment at the bottom. Appears that the cork and capsule are intact. He’s asking what we think about it. The wine is https://www.cellartracker.com/wine.asp?iWine=704664

Any thoughts? Is this likely to be “interesting” or more likely to be vinegar? @rpm @TerceroWines @ScottHarveyWine and where’s Peter when you need him?