Interesting, thanks. At the end (~6:50) there are a few seconds about the aerodynamics of the 'wing', which had been my first question.

Did you forget about adjustable pitch propellers? We have managed to use human-scale ones even to synthesize low-frequency audio by building a sealed room and putting a reverse-thrust-capable one on the only opening of that room (besides a closed door). It spins and the pitch is adjusted to modulate thrust in response to the sound signal.

Those rotary woofers deliver supposedly good distortion up to their rotation frequency; 13 Hz / 800rpm seems common. For reference, a tail sitter propeller would probably spin faster than that, though even this is plenty to control the aircraft. A blade design using a servo flap easily keeps up with those control speeds, and could likely even offer thrust vectoring like the rotor of a helicopter (could eliminate the flaperons).

The real enemy is power-to-weight ratio.

Fun fact: the F-117 had its first flight in 1981 and has already been retired from combat duty for nearly 15 years[0]. So “new” is perhaps not quite the right word to describe it.

[0] https://en.m.wikipedia.org/wiki/Lockheed_F-117_Nighthawk

yeah there were a handful of tailsitter designs that era. Cool concepts but pretty much all had an achille's heel or two.