timezone on Unix can differ per year

program.cs

using System;
using Newtonsoft.Json;

namespace jsonTimeZone
{
    //https://stackoverflow.com/questions/65436081/date-deserialization-difference-between-kestrel-on-windows-and-kestrel-on-macos
    class Program
    {
        static void Main(string[] args)
        {
            var settings = new JsonSerializerSettings()
            {
                DateTimeZoneHandling = DateTimeZoneHandling.Local,
            };
            for (int q = 1912; q < 2020; q += 10)
            {
                var content = string.Format(@"""{0}-01-01T21:00:00.000Z""", q);
                var dob = JsonConvert.DeserializeObject<DateTime>(content, settings);

                Console.WriteLine( $"dob: {dob.ToString("yyyy-MM-dd HH:mm:ss.fff")} - {dob.Kind}");
            }
            Console.WriteLine(TimeZoneInfo.Local);
        }
    }
}
// Ubuntu 20 output is:
// (UTC+02:00) Eastern European Standard Time
// dob: 1912-01-01 23:02:00.000 - Local
// dob: 1922-01-01 23:02:00.000 - Local
// dob: 1932-01-02 00:00:00.000 - Local
// dob: 1942-01-01 23:00:00.000 - Local
// dob: 1952-01-02 00:00:00.000 - Local
// dob: 1962-01-02 00:00:00.000 - Local
// dob: 1972-01-02 00:00:00.000 - Local
// dob: 1982-01-02 00:00:00.000 - Local
// dob: 1992-01-01 23:00:00.000 - Local
// dob: 2002-01-01 23:00:00.000 - Local
// dob: 2012-01-01 23:00:00.000 - Local


// Windows 10 output is:
//dob: 1912-01-01 23:00:00.000 - Local
//dob: 1922-01-01 23:00:00.000 - Local
//dob: 1932-01-01 23:00:00.000 - Local
//dob: 1942-01-01 23:00:00.000 - Local
//dob: 1952-01-01 23:00:00.000 - Local
//dob: 1962-01-01 23:00:00.000 - Local
//dob: 1972-01-01 23:00:00.000 - Local
//dob: 1982-01-01 23:00:00.000 - Local
//dob: 1992-01-01 23:00:00.000 - Local
//dob: 2002-01-01 23:00:00.000 - Local
//dob: 2012-01-01 23:00:00.000 - Local
//(UTC+02:00) Helsinki, Kyiv, Riga, Sofia, Tallinn, Vilnius