Hm. Cheerleading is obviously physically difficult, and meets the demands of a sport, but I do agree with the reservations others have. Cheerleading exists in other countries (I know some people who do it here in Australia) but I’m sure the vast majority is done in the U.S. I also struggle to separate cheer as a sport from cheer as a rather weird institution before American football games. As far as I am concerned, cheerleading is the cultural (and messier) version of acrobatic gymnastics, which of the pair is the one which should be in the Olympics.
I feel the same way about skateboarding. I enjoy watching it and I don’t deny its physical difficulty, but it’s primarily a Western cultural phenomenon and street event rather than a formal sport.
If we added everything physically difficult to the IOC sports list, it would be a mile long, and the inclusion/exclusion of different sports in the Olympics would be increasingly arbitrary. It is already difficult to find countries to host the Olympics.
That does raise the question of how we decide what sports are worthy of being in the Olympics. Presumably we prefer a test which is able to evolve with the times. My suggestion would be that the activity must be trained for primarily formal competitive purposes.