This was my thought - it's an awesome read and 3D printing definitely has its place, but its strength is generally in one-off or very-short-run custom items rather than building mass produced parts.
It's also worth thinking about this in context: Even without offering any customization, the cost to buy my part in batches of ~40 actually works out pretty well (caveat: this is a decidedly high end bike part). With forged, machined, and composite parts, that's an extremely low purchase quantity; in most cases, you'd never come close to amortizing the tooling & setup time.
That said, I'm definitely interested in exploring other products, and new business models for how to sell them. This part is just the first step in that process :)