How to properly get rid of this concurrency compile error?

Using Swift
1 
@MainActor
class A {}

class VC: UIViewController {
  let foo: A

  init() {
    self.foo = A() // Error: Call to main actor-isolated initializer 'init()' in a synchronous nonisolated context
    super.init(nibName: nil, bundle: nil)
  }

  @MainActor
  init() {
    self.foo = A() // Compiles
    super.init(nibName: nil, bundle: nil)
  }

  init(_ void: Void = ()) { 
    self.foo = A() // Compiles
    super.init(nibName: nil, bundle: nil)
  }
}

I get that A() should be called on a main-actor initializer, but why the first initializer doesn't inherit the @MainActor from UIViewController? and why the Void parameter gets rid of the error (even with -warn-concurrency)?

Note: if I annotate VC with @MainActor, I get the same error for the super.init in the first initializer, and the third initializer still works.