I feel stupider for having watched this. This guy picks up a Fuji X100s when he personally isn't bothered by any of big reasons why someone actually WOULD pick one of these up. Then inquisitively explains why it doesn't work for him, because, you know....it was addressing problems he didn't have in the first place to have warranted the camera.
1. The size. The size of a DSLR is one of the primary reasons anyone considers this camera. I just picked up an X100T for this exact reason. I LOVE my Sigma 35 and 5D3 combo, and wanted something that would give me similar results but in much more compact size that I would actually take places. If I didn't have a problem with my 5D3 and didn't mind taking it places I would have never bought the X100T. The 5D3 takes amazing pictures and I don't pretend the Fuji could replace that, but it gets very close.
2. The iPhone. Again, different purposes. If snapshots are your only objective, then yes, of course you don't need an X100. If, however, you want DSLR quality bokeh, the ability to shoot good quality in much worse lighting conditions, and want the option to print or even license your photos, that X100 sure will beat out the iPhone in image quality.
3. Weather sealing. My 5D3 is not sealed with the Sigma lens. Sure some of Canon's lenses are, but not all of them. Neither is an iPhone. This camera is no different.
TLDR Version: Guy picks up camera he didn't need, doesn't recommend it because he didn't need it