There's a lot of difference in what you get depending on what exactly you're getting. I suspect that the vast majority of "kobe" beef sold in the US isn't. A lot will have some kind of Wagyu-type cow, maybe sometimes actually imported from Japan (but my guess would be less than 0.01%). When in the US the term Wagyu/ kobe is used, it's mainly referring to the A4/ A5 high fat type cut where you really do want the fat to be rendered down. Assuming that you're looking at a super fatty carpaccio, I'd like someone to at least take a blowtorch to it if it's not going to be cooked.