As a self proclaimed seeker of truth you sure did little homework on this to think its a wind turbine, at the very least you could have watched the video in its entirety. And here you are talking about how the greats could have missed something so obvious and you are missing what is in plain sight. But I digress, I guess some nuts can only be cracked by a hammer. I hope your nut is ready for said hammer because its going to be a big one.
The propeller is connected to the wheels, so any rotation of the propeller causes the machine to move forwards or backwards, with only the forces of friction to overcome, since movement only requires energy to overcome friction or to accelerate.
What is friction? There are two significant points to consider: the friction of the wheels on the ground, which is absolutely essential otherwise the machine would slide with the slightest wind.
The friction of the wind on the blades, which translates into an overall force in the direction of the wind, and through the deflection of the wind by the inclination of the blades, into a transverse force that turns the propeller.
When the machine is stationary, it is locked to the ground by the friction of the wheels. The transverse force tends to turn the propeller, which tends to turn the wheels, which tend to move the machine. For the machine to move forward, this force must be greater than the force exerted by the wind on the machine as a whole. Since the gear ratio between the propeller and the wheels can be arbitrarily set by a set of gears or pulleys, the force that can be exerted to turn the wheels in order to move can be arbitrarily large.
The larger the ratio (many propeller revolutions for few wheel revolutions), the greater the force but the slower the machine will move. The smaller the ratio (few propeller revolutions for many wheel revolutions), the faster the machine will move, but the force will be weak, and if it's too weak, it won't surpass the overall force exerted by the wind on the whole machine.
The efficiency of the machine is therefore determined by this ratio and the reduction of all other sources of loss, such as axle friction.
An arbitrarily large force can be obtained from a small force, but their work will be the same. As for the question of wind speed and machine speed, they are not linked in any way as long as there is a difference, i.e. a non-zero relative speed of the wind in relation to the machine, which makes it possible to draw energy.
Finally, the direction of motion can be forward or backward, depending on the technical realization, but this doesn't change the question as long as the relative wind speed is not zero.
Once again, if you don't understand all this, it's because, like many others, you haven't yet grasped the difference between force and energy/work, and that relative speed is mainly related to energy, not force.
Contrary to your answer, the comparison with a wind turbine is perfectly relevant to the video if you understand the general principles involved, and answers your previous question "where did that kinetic energy come from?". It's only you who doesn't see the connection and isn't trying to understand, prefering to look anywhere for anomalies in physics when it's ignorance of its laws that generates the illusion. Don't blame me for your lack of understanding, it's pathetic.