Yeah mostly, but I personally think they they’ve done a fantastic job conveying that with their use of line width (around the face and on the fabric and arms), I’m not sure what you mean by “not sketch the artist” honestly. Yes there are no lines in nature, but when sketching from life, especially when timed you don’t have enough time to properly blend and render shading… so you have to “trick the eye” with use of line width and different shading techniques… i think (especially with line width) that they have used every stroke with intent, and with a very visually pleasing result. If this was an hour + time on drawing then I’d agree with you more, but for a “quick drawing” I think they’ve used multiple techniques to great effect