Using Mediator to call async method from within a data-bound property setter

Question

I need to call an async method ConnectToLibrary once a book is selected, meaning once SelectedBook property is set. I saw many solutions. But all of them require hacks or starting a task/thread from a setter. My question, what's wrong with using a mediator like Messenger from Microsoft Toolkit.Mvvm?
I can just register a callback to ConnectToLibrary with Messenger.Register<...BookSelectedMessage>(...ConnectToLibrary...) and then call Messenger.Send(new BookSelectedMessage()) from the SelectedBook 's setter.
Is this the correct way to do this in MVVM?

public MyViewModel : ObservableRecipient
{
    public ObservableCollection<BookInfo> Books { get; } = new();    

    private BookInfo _selectedBook;
    public BookInfo SelectedBook
    {
        get => _selectedBook;
        set => SetProperty(ref _selectedBook, value);
    }

    private async Task ConnectToLibrary(BookInfo info)
    {        
        await START_SOME_ASYNC_METHOD();
    }
}

Answer 1

Nothing. In either case any Exception is swallowed. And since you are asking, what's wrong with starting a thread from a Setter ? It sounds to me like the requirements of your app require this anyway, no?