I went custom with my most recent frame purchase specifically to avoid all of the internal shenanigans (and also because real CX geo is getting harder and harder to find). I want maintenance to be easy as possible in a bike where aero gains will never come into play.

You know that there are people still using mechanical groups, right? Not everyone wants to ride an e-group. Further, I’d wager that the fraction of folks interested in metal bikes that also use mech groups is higher than it is for folks riding CF bikes.

Mech vs e-groups aside, there’s a significant fraction of folks that aren’t interested in the higher maintenance costs of totally integrated systems and that extra faff that comes with them.

Exactly. Internal “cable” routing is going to be like those words that stick around despite that technology not being present. Like pencil lead, gas pedal on an EV, etc. More and more bikes are essentially cableless.

For hydraulic brakes, as long as the cable does not get kinked, it doesn’t care if there are aggressive bends.

You know most of the groupsets are electronic now and most of them even have wireless shifters, right? So no impact in shifting quality using internal routing.

Good question. The tight turns the cable and housing would have to make in such a bike would tend to negatively impact shifting. IMHO, the big head tubes required as well as the larger–bulbous–stems and spacers don’t mesh well with the look of a metal frame.