[unification_fan]

Everyone calls them sound cards and they are marketed as sound cards therefore they are sound cards. An USB audio interface is literally just an external sound card.

Regardless, I did a quick google search to confirm that my usage of the term was correct and yep - "sound card" and "audio interface" are used interchangeably. So no one cares about your technicalities.

[MrSkelter]

This isn’t true in professional circles at all. Audio interfaces are external. There is no need to collapse the language it confers no benefit.

Audio interfaces are external because it makes it so much easier to shield them properly. Thus if someone wanted to sell a computer for professional audio work with a sound card there would be a problem.