The problem with pictures is that it's hard to tell what happened just prior to and after the shot was taken.
Regarding the TBD, it's not really possible to tell how high he is. It depends a lot on the height of the camera. If the plane is low, then consider that the torpedo is slung with the nose down rather than perfectly horizontal.
Regarding the G4Ms, it's quite possible their torpedoes did not arm. It's also possible that they are hanging low to avoid flak and will bounce up at the last possible moment to release their torps. One has to ask because there is also a Betty that is close to the appropriate drop height.
The lowest drop-height mentioned that I can find is 23 meters, the vast majority of sources saying 30 meters or so. I can't find anything describing successful wave-height releases. Even if it was even possible by going slower, you would be putting yourself at great risk to enemy fire by doing so.
At 1:00 you can see the torpedo jump out of the water because it was released too low.
Regarding success at Pearl Harbor, of 40 torpedo planes present, only about 15 fish hit ships (which were totally stationary btw).