I don’t want to sound like a Fuji fanboy here as I’m not but this is not my experience at all. The Fuji AWB nails it pretty much every single time for me whereas my Sony always needs tweaked in post. I wonder if it’s because you were using a first generation Fuji and not the newer models?
He was using an xt-1 so it's possible...but we also shot in a lot of mixed light, and used speed lights and off camera lights (he has a godox trigger so he was firing my lights). It's pretty much expected that AWB would miss it's mark from time to time...and stylistically, sometimes I drift away from whites being pure 4500k. Not a big deal though....white balance corrections are pretty simple. Color casts and things like really hot yellows when your subject is in the shade and the sun is hitting things in the background are more difficult, and still need to be dealt with regardless of what camera is being used.
I'm not bashing Fuji, but I also don't see anything special about the Fuji colors that are so highly regarded. Much like my comments about Canon colors when I had a Canon second shooter, when it comes to raws, I don't really find one to brand to be better than the other. The baselines are different, but in terms of colors, I can get very close to the same end result in post.
One thing I will say is that the Fuji 56 1.2 is really nice lens. Really sharp and great rendering