Seems to me that one of the most common comments after meeting an actor is “He/she was shorter than I expected.” It’s especially true if the actor is known for heroic leading roles, like Robert Downey Jr., or explosive or driven characters, like Jack Black. And it seems that everyone knows that Tom Cruise is not tall, but he’s been the biggest star in the world.
Not all stars are short — Liam Neeson and Tilda Swinton, for instance, are very tall — but Hollywood appears to have a relatively high proportion of smaller people like Salma Hayek, Daniel Radcliffe and Eva Longoria.
In my opinion, a key factor is what screenwriter William Goldman called “early entry.”
Acting — unlike, say, engineering or law or medicine — often needs people who are very young. Many productions have roles for children or young teenagers.
But a production that hires a child or young teen faces a lot of challenges. A kid actor may have less maturity, training and professional discipline than adults. And the law prevents a kid from working as many hours per day.
But if a performer’s a legal adult who looks younger — for instance, an 18-year-old who can play 14 — then several problems with hiring kids go away. Short actors have an advantage in that situation. They get opportunities that other another actor may miss.
And if they’re really good, they can rise in their profession, if not in their physical stature.