not a fan..
we have done this and sewed the fullness in by machine.. no hand work.
in fact i will bet there may even be a row of machine stitches in the sleeve set as well on the first shirt shown.
the second set on cravate noir. work for him
as he has very wide shoulders and a very narrow chest
but the armhole seems too deep for this technique.
the idea is that the armhole is smaller and closer to the body, while the fullness of the top sleeve allows for movement
That really is a bit too much.
I can't imagine why you wouldn't make the sleeve a lot smaller, especially with the torso cut so trim.
Have to think you'd also have a much better range of motion with a smaller armhole and narrower sleeve.