I'm not going to bother reading the whole thread but I think its popularity is mostly due to the fact that it found a niche in the US market that the most of the major manufactures had abandoned, - a steel drop bar road bike with lots of tire clearance. The fact that it uses bar ends rather than STIs helps its utilitarian image.

I understand their appeal but there are now quite a few choices in that space. I'd like a similar bike with an aluminum frame and a belt drive but I'm too cheap to spend much on it. I have a bike that's close enough.