What is a proper way to scale PKCanvasView (UIScrollView)

Question

I have PKCanvasView in my iPad app. When the user rotates the iPad - I need to scale the Canvas and all the strokes accordingly.

So far I've found two ways to scale a PKCanvasView, first with a .zoomScale:

GeometryReader { geo in
// Canvas View goes here...
}
.onChange(of: geo.size) { newSize in
    let canvasScale = newSize.width / myDefaultCanvasWidth
    
    canvasView.minimumZoomScale = canvasScale
    canvasView.maximumZoomScale = canvasScale
    canvasView.zoomScale = canvasScale
}

Second with CGAffineTransform:

//For short:
let transform = CGAffineTransform(scaleX: scaleWidth, y: scaleHeight)
canvasView.drawing.transform(using: transform)

What is the difference between those two methods and which one is correct and preferable?

Thank you.