The F-35 also has a better (lower) radar cross section than the X-32 which had exposed turbine blades. And crucially, the prototype X-32 failed to demonstrate simultaneous VTOL and supersonic flight, while the X-35 did. Seeing as this was the main characteristic the military wanted, this is a pretty significant shortcoming.
It's true that more conservative designs have historically prevailed over technically more impressive exotic designs. I think this is not about looking cooler (the YF-23 looked cooler than the F-22 IMO), and more about risk aversion when billions of dollars and people's lives are on the line. And there are still exceptions to this like the B-2. Although it drew on experience from the XB-35.
The production version of the X-32 was supposed to have a radar blocker fitted over the front of the turbine to hide the blades. Probably not quite as effective as the serpentine duct seen on the F-22 and F-35, but it would significantly reduce returns.
It's true that more conservative designs have historically prevailed over technically more impressive exotic designs. I think this is not about looking cooler (the YF-23 looked cooler than the F-22 IMO), and more about risk aversion when billions of dollars and people's lives are on the line. And there are still exceptions to this like the B-2. Although it drew on experience from the XB-35.