You have a valid point regarding terminal velocity dives. During the early thirties, test pilots (at least according to the movies) would climb the experimental aircraft as high as it would go and put it in a vertical dive (presumably with the engine at idle). When it wouldn't accelerate any more the drag was equal to the weight which seemed to be important to the early engineers. The drama was all in the resulting pull out which some made and some didn't. I don't seriously think that they still do this with airplanes like the FA-18.

When the aircraft approaches terminal velocity, fuel could indeed fall to the front of the tank. With a lightly loaded biplane, or even something like a SIG Senior, you might approach terminal velocity but the initial altitude would likely higher than most folk ever fly. For a typical sport, aerobatic, or 3D type I doubt it would ever happen.

When an aircraft is slowing down for a landing, the deceleration is not enough to do more than slightly slope the fuel level. If the tank is almost empty, it could cause a shutdown

The point is that wings isn't missing anything. It is not a problem.