Can’t comment on Detroit as I’ve never owned a Bootlegger, but SB J100 is not based on BR. It has a very different pattern and fit.
What makes me think that it's not only the shirt problem are the last few photos of his hip area close-up. You can tell that the jacket does not cover his belt.^^
It's not the jacket that is too short, it is dude's shirt that is entirely too long. He's shooting for the "effortless cool" look, and he misses.
The Detroit is in CXL steerhide; the J100 is in epsom.
Definitely not. The jacket ends at the top of the belt and would be a good inch too short for me. Maybe that's why the shirt hangs out, to visually conceal that. But then I would not take a contrasting color, but rather, for example, a dark wool vest. But tastes are different.
I think straight front hem works only with tucked in shirts. Some front drop hem works with untucked shirts, but only if the shirt was designed to be untucked to began with. The traditional dress shirt with the low half moon hem just aren't meant to be untucked unless the front drop is at least 3.5" plus (like on my FCL jacket).
The easiest way is to just tuck in the shirt when it feels too long. And the belt is actually the hero in all situations, tuck or no tuck, straight or curved hem.
Yeah I also get the "untuck fit" shirts now. They also work tucked in, just shorter than the regular button downs with the huge half circles of material front and back. Lewis looking great!