奇怪的行为确实。我也可以复制那个错误（ish）。但是好消息是，你可以为你的目的使用转换器。
在maui项目中创建一个名为Converters的文件夹
创建这2个类

速度转换器.cs

namespace MauiApp.Converters;

class SpeedConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        string speed = (string)value;
        return $"~{speed}% Completed";
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

状态转换器.cs

class StatusConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        string status = (string)value;
        return $"({status})";
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

现在，在XAML文件中导入该命名空间

<ContentPage
    xmlns:converters="clr-namespace:MauiApp.Converters">

并像这样更改标签的文本绑定

<Label
  Margin="0,0,5,0"
  FontAttributes="Bold"
  FontSize="Body"
  HorizontalOptions="Center"
  Text="{Binding Speed, Converter={converters:SpeedConverter}}" />
        
<Label
  FontAttributes="Bold"
  FontSize="Body"
  HorizontalOptions="Center"
  Text="{Binding Status, Converter={converters:StatusConverter}}" />