I'm assuming he's talking about the old hardware data cassette vs the software project of the save name?

https://en.wikipedia.org/wiki/Commodore_Datasette vs

https://datasette.io/

My favourite Datassette is the electronic artist.

https://datassette.bandcamp.com/

https://musicforprogramming.net/

I’m assuming they’re just taking about the word dataset.

Either way feels ridiculous, but the human in me wants to know which it is ^_^