Well, apparently fiat is the only company with any money in crypto. Mercedes, Volvo, Kia - none of these get to play.
I suspect the term 'fiat' is explicitly used to ensure that even those who consider crypto currencies a realistic future replacement for fiat (which, btw, is already an issue as money <> currency, but let's skip over the pedantics) get to distinguish between the two categories.
One is regulated and has at least *some* guarantees, the other is a Wild West style combination of a pyramid scheme and gambling with massive ecological problems. The two worlds do have in common is that in both you can lose your shirt to unscrupulous operators, but the likelihood of recovery is a bit higher with fiat.