Using ConfigurationBuilder with a json file to add null to list

I am trying to put a list of enums into appsettings.json that will be iterated through at one point in the code. The problem is that if I put a null value into the list in the json file, it does not populate a null value into the list when the Settings are loaded from the file.

minimum code example:

using Microsoft.Extensions.Configuration;
using System;
using System.Collections.Generic;

class Program
{
    static void Main(string[] args)
    {
        var builder = new ConfigurationBuilder().
            AddJsonFile($"appsettings.json");

        var config = builder.Build();
        
        var test = config.GetRequiredSection("Settings").Get<Settings>();
        test.EnumList.Add(null);
    }
}

class Settings
{
    public enum EnumValues
    {
        Value1,
        Value2
    }
    public List<EnumValues?> EnumList { get; set; }
}

json file:

{
    "Settings": {
        "EnumList" :  [null, "Value1"]
    }
}

The test.EnumList.Add(null) will predictably and correctly add a null to the list, however, there will be no null in the list before that line, despite being in the json file. I would like to actually be able to put a null in the json file and have it show up in list.

How can I do this? I've hunted for a bit and I've come up with nothing.