The problem with Metatype as a keyword is that it's one level of abstraction too far up.
Think about a typical type name: Int, UIViewController, Record. What you'll notice about the type name is that it's a description of the instances of that type, not a description of the type itself. You don't see types with names like IntStruct or UIViewControllerClass except in beginner code.
Just as UIViewController is a class, UIViewController.Type (to use current terminology) is a metatype. But that doesn't mean the word "metatype" belongs in its name, any more than the word "class" belongs in UIViewController. The type name describes the instances of that type, and the instances of UIViewController.Type are types, so Type, not Metatype, is the appropriate word.
That's why I say that we should use Type<T>, not Metatype<T>—because Metatype<T> would have the same mistake as UIViewControllerClass.