Real French brie is unpasteurized, which is illegal in the US. See https://theculturetrip.com/north-america/usa/articles/fancy-...
So no, what you buy as brie, if it went through official US import channels, is not real Brie. Now how much is the real difference in taste is another topic, but we take protecting traditional methods of making these things very seriously here in Europe. Very anti-race-to-the-bottom approach.