Is there anything funny about disability? Not the disability itself and not necessarily the disabled person, but the situations we find ourselves in are often funny, and everybody often laughs at the same things.
Humor is a serious thing. I like to think of it as one of our greatest earliest natural resources, which must be preserved at all cost.
James Thurber, American writer (1894-1961)
Let's look at the wheelchair careening down a slope. Funny or frightening? What if it's a car, kids in a wagon, someone skiing or even someone rolling in a tire. This gag is a staple used over and over in movies and sitcoms. A Psychology Today article, What's Your Humor Style, mentions that the ancient Greeks thought humor was aggressive, and this particular gag certainly seems to be so. The article tells us this is only one type of humor.