using System;

using System.Diagnostics;

public class Program

{

    public static void Main()

    {

        BoolTestClass instance = null;

        Console.WriteLine($"{instance == null}: instance == null");

        instance = new BoolTestClass();

        if(instance?.NonNullableBool) {

            Console.WriteLine($"{instance == null}: instance == null");

        }

    }

}

​

public class BoolTestClass

{

    public bool NonNullableBool { get; set; }

    public bool? NullableBool { get; set; }

}