iOS 15 only view modifier causes crash on iOS 14 even with if #available(iOS 15.0, *) – Ios swift

I’m using SwiftUI’s drag & drop modifiers. Since, iOS 15 gives an option to customise the onDrag modifier with a preview I’m using it as shown below.

Issue: I’ve a if #available(iOS 15.0, *) guard to choose the view for different iOS versions. But, somehow my app on iOS 14.x crashes due to an EXC_BAD_ACCESS (code=1, address=0x0) error since it tries to find the new API but it is not present in iOS 14.

@ViewBuilder
private func getRoutineCard(routine: RoutineInfo) -> some View {
    if #available(iOS 15.0, *) {
        newRoutineCard(routine: routine)
    } else {
        oldRoutineCard(routine: routine)
    }
}

@available(iOS 15.0, *)
@ViewBuilder
private func newRoutineCard(routine: RoutineInfo) -> some View {
    RoutineCard(routine: routine)
    // This modifier is what crashes the app on iOS 14.x
    // onDrag with a drag preview view not available in iOS 14.x
        .onDrag({
            dragReorder(draggedRoutine: routine)
        }, preview: {
            RoutineCardDragPreview(routine: routine)
        })
        .onDrop(of: [.text], delegate: ReorderDropDelegate(isDragging: $isDragging, draggedItem: $draggedItem, item: routine, haptics: haptics, onMove: updateOrder(routine:order:)))
}

@ViewBuilder
private func oldRoutineCard(routine: RoutineInfo) -> some View {
    RoutineCard(routine: routine)
        .onDrag { dragReorder(draggedRoutine: routine) }
        .onDrop(of: [.text], delegate: ReorderDropDelegate(isDragging: $isDragging, draggedItem: $draggedItem, item: routine, haptics: haptics, onMove: updateOrder(routine:order:)))
}

What I’m looking for: A workaround to choose between the two views based on the iOS version without causing a crash.