By the way, I call this PS fold The Great Wave off Kanagawa.
Warning: Spoiler! (Click to show)
I call it the fold.
There's no "flare." It must be the camera angle.
It's really just an old-fashioned "full break." If you search the forum for "break," "trouser break," "pants break," etc., you'll no doubt find many discussions of the subject.
I like it especially when (1) I'm dressing particularly conservatively, and (2) the trouser width (9 inches here) and the fabric will accommodate it.
That's a full break on a largeish bottom relative to your shoe size, and probably relative to the knee on the trousers. You can have a full break with a lot more taper than that. It's not a very SF look, though I don't mind it if it's proportionate to the jacket and to the shoes.
Simply elegant ...
It looks great, and I love the briefcase, but (and this might be the angle) do the trousers look a little short?