В .net MAUI какой элемент управления выбрать номер для маленького экрана?

Правильный подход — использовать вертикальную карусель (док).

    <ContentView.Content>
        <StackLayout VerticalOptions = "Center" HorizontalOptions = "Center" Spacing = "0">
            <CarouselView ItemsSource = "{Binding Source = {x:Reference Root}, Path=Numbers}" 
                          CurrentItem = "{Binding Source = {x:Reference Root}, Path=Number}"
                          IsSwipeEnabled = "{Binding Source = {x:Reference Root}, Path=IsSwipeEnabled}">
                <CarouselView.ItemsLayout>
                    <LinearItemsLayout Orientation = "Vertical" />
                </CarouselView.ItemsLayout>
                <CarouselView.ItemTemplate>
                    <DataTemplate>
                        <Label x:Name = "NumberLabel" Text = "{Binding ., StringFormat='{}{0:D2}'}" FontSize = "Title" VerticalOptions = "Center" 
                               HorizontalOptions = "Center" HorizontalTextAlignment = "Center" VerticalTextAlignment = "Center"
                               WidthRequest = "50" TextColor = "White"/>
                    </DataTemplate>
                </CarouselView.ItemTemplate>
            </CarouselView>

            <BoxView HeightRequest = "2" BackgroundColor = "White" VerticalOptions = "Start" HorizontalOptions = "FillAndExpand"/>
        </StackLayout>
    </ContentView.Content>

public partial class NumberPicker : ContentView
{
    public static readonly BindableProperty NumberProperty = BindableProperty.Create(nameof(Number), typeof(int), typeof(NumberPicker), 0);
    public static readonly BindableProperty IsSwipeEnabledProperty = BindableProperty.Create(nameof(IsSwipeEnabled), typeof(bool), typeof(DigitPicker), true);

    public List<int> Numbers { get; } = new (Enumerable.Range(0, 59));

    public bool IsSwipeEnabled
    {
        get => (bool)GetValue(IsSwipeEnabledProperty);
        set
        {
            SetValue(IsSwipeEnabledProperty, value);
            OnPropertyChanged(nameof(IsSwipeEnabled));
        }
    }

    public int Number
    {
        get => (int)GetValue(NumberProperty);
        set => SetValue(NumberProperty, value);
    }


    public NumberPicker()
    {
        InitializeComponent();
    }
}