为什么不使用Removed方法删除genereic列表中的项目？

I have this class.

我有这门课。

public class Foo
{
    public Guid Id { get; set; }

    public override bool Equals(object obj)
    {
        Foo otherObj = obj as Foo;

        return otherObj == null && otherObj.Id == this.Id;
    }

    public override int GetHashCode()
    {
        return this.Id.GetHashCode();
    }
}
public class Foo