For me it would be too short for work, same reason as others already stated - would likely not pass the "sit" test. And to pass that test, I find a lot of times it's not even the length that is the issue, it's the cut of the skirt, and also the material. Because I am apple shaped with flat rear, a skirt like this may appear to be fine when I sit (not exposing too much thigh) but it'll hike up too far in the rear (the belly throws it off in the back), and it feels gross sitting in public spaces! Mind you, I also no longer wear shorts except for gear...
When I think about the handful of work dresses I own that hit above the knee, they are all styles that surrender the waist, or are fluid materials/fits, like an A-line shape. These pass the sit test.
When I wear such a dress for work, I pair with dark tights to cover the exposed skin, and I'd be sure to wear a high neckline as well.
I am okay with exposing some skin at work -- I do look far better in a V neck rather than a crew neckline --- but for me it's about balance. If I'm exposing bare leg, then I cover up the top (with higher neckline or a scarf). If my legs are fully covered, then I feel more okay with a V-neck.
Though I gotta say that wearing midi & maxi lengths this summer is making me feel that my knee-length dresses are too short!
