AdaptiveGridView.ItemContainerStyleSelector doesn't work

MainPage.xaml

<Page
    x:Class="App1.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:App1"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:toolkit="using:Microsoft.Toolkit.Uwp.UI.Controls"
    mc:Ignorable="d">

    <Page.Resources>
        <local:ThingStyleSelector x:Key="ThingStyleSelector">
            <local:ThingStyleSelector.EvenStyle>
                <Style TargetType="GridViewItem">
                    <Setter Property="Background" Value="Red"/>
                </Style>
            </local:ThingStyleSelector.EvenStyle>
            <local:ThingStyleSelector.OddStyle>
                <Style TargetType="GridViewItem">
                    <Setter Property="Background" Value="Green"/>
                </Style>
            </local:ThingStyleSelector.OddStyle>
        </local:ThingStyleSelector>
    </Page.Resources>
    
    <StackPanel Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
        <toolkit:AdaptiveGridView DesiredWidth="100" ItemContainerStyleSelector="{StaticResource ThingStyleSelector}" ItemsSource="{x:Bind Things}">
            <toolkit:AdaptiveGridView.ItemTemplate>
                <DataTemplate x:DataType="local:Thing">
                    <TextBlock Text="{x:Bind Num}" />
                </DataTemplate>
            </toolkit:AdaptiveGridView.ItemTemplate>
        </toolkit:AdaptiveGridView>

        <GridView ItemContainerStyleSelector="{StaticResource ThingStyleSelector}" ItemsSource="{x:Bind Things}">
            <GridView.ItemTemplate>
                <DataTemplate x:DataType="local:Thing">
                    <TextBlock Text="{x:Bind Num}" />
                </DataTemplate>
            </GridView.ItemTemplate>
        </GridView>
    </StackPanel>
</Page>

MainPage.xaml.cs

using System.Collections.ObjectModel;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;

namespace App1
{
    public sealed partial class MainPage : Page
    {
        public MainPage()
        {
            this.InitializeComponent();

            Things = new ObservableCollection<Thing>
            {
                new Thing(null),
                new Thing(1),
                new Thing(1),
                new Thing(2),
                new Thing(3),
                new Thing(3),
                new Thing(4),
                new Thing(6)
            };
        }

        ObservableCollection<Thing> Things { get; }
    }

    public class Thing
    {
        public Thing(int? num)
        {
            Num = num;
        }

        public int? Num { get; set; }
    }

    public class ThingStyleSelector : StyleSelector
    {
        public Style EvenStyle { get; set; }
        public Style OddStyle { get; set; }

        protected override Style SelectStyleCore(object item, DependencyObject container)
        {
            if (item is Thing t)
            {
                if ((t?.Num ?? 0) % 2 == 0)
                    return EvenStyle;
                else
                    return OddStyle;
            }

            return base.SelectStyleCore(item, container);
        }
    }
}