Why are Heavy Skiers Fast?

Why are heavier skiers faster than lighter ones, and heavier cyclists faster than lighter cyclists? In this video, I'll be exploring the physics of why this is so.
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Ever since the advent of human curiosity about how our world works, man has pondered whether heavier objects fall faster than lighter objects. Aristotle hypothesized that objects fall at a speed proportional to their mass, and this seems to be the case with cyclists and skiers, but is it really that simple?
The hypothesis that Aristotle proposed seems to be logical, as a hammer will definitely fall faster than a feather when both are dropped. However, it took until the time of Galileo for this idea to be rejected. Galileo is well known to us for his ideas that seemed controversial at the time, but have laid the foundations for astronomy and physics, and his hypothesis on gravity was no exception. Galileo believed that, contrary to Aristotle’s idea, all objects will fall at the same rate, regardless of their mass. Under this rulebook, the hammer would fall alongside the feather and so hit the ground at the same time… which seems completely absurd, as we know that is not true! How does this work then?
The missing element to this scenario that we disregarded is air resistance, as we assumed that the only force acting on each of the hammer and feather is that of their own weight. As air resistance increases with speed, and the feather has a much lower weight than the hammer, it reaches a terminal velocity, where the forces of weight and drag are equal, at a much lower speed than the hammer, and so falls slower. If we conducted this experiment in a vacuum, they would hit the ground at the same time, and this is an experiment that was even run on the moon for verification.
Now picture two skiers standing on a slope, one of mass 120 kg, and the other with half the mass. We would expect their initial accelerations to be different, as they aren’t hammers and feathers moving in freefall, but if we resolve each of the forces of weight and friction, we see something surprising. Weight is simply the product of mass and g, the gravitational field strength on earth, but since we are considering a slope, we can split the weight into two component forces, which will add to give the same thing. One force will be perpendicular to the slope, and the other parallel to the slope. Their relative magnitudes will depend on the angle of the slope, as if it is flat, there will be no component acting parallel to the slope, and if the slope is vertical, all of the weight will be acting parallel to it. There is also another force acting on the skier, known as normal contact force, and this force is the reason why you don't sink through the ground when you stand on it. This force is equal to the perpendicular component of weight, as the skier does not sink into the mountain, whatever the angle. Our last force to consider is that of friction, which is equal to a constant multiplied by our normal contact force. It follows that maximum friction occurs when the normal contact force is greatest, which happens when the slope is flat, and is at a minimum when the slope is vertical. If we resolve these forces parallel to the slope, and apply Newton’s second law, which states that the force on an object is directly proportional to the rate of change of its momentum, we see that rearranging for acceleration gives the same expression for both the heavier and lighter skier, so initial acceleration is only affected by the angle of the slope. (Disregarding static and dynamic coefficients)
However, initial accelerations are not what we are interested in for determining outright speed, and so we need to add the complication of air resistance. Similar to the feather, the lighter skier has a lower weight, and so the force of air resistance required to give zero overall force on the skier occurs at a lower speed than for the heavier skier. This means that, given their positions and frontal areas are the same, a heavier skier will always be faster than a lighter one in a straight line. This graph shows mass against maximum speed for a skier travelling down a piste at 45 degrees. It clearly shows that an increase in mass results in an increase in speed, but since drag increases with velocity squared, and weight increases linearly with mass, a larger increase in mass is required for a given increase in speed at higher speeds. The next graph shows how speed increases with slope angle for skiers of mass 60 kilos and 120 kilos, again showing that the heavier skier is always faster, no matter the slope angle.

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Thank you for that! I had an argument with some friends, and now I see why I was wrong.