C# value types vs reference types performance

ValueTypeBenchmark.cs

using System.Linq;
using BenchmarkDotNet.Attributes;

/// <summary>
/// 1M, MB Pro M3
/// | Method      | Mean     | Error   | StdDev  | Ratio |
/// |------------ |---------:|--------:|--------:|------:|
/// | TestValType | 530.2 us | 6.94 us | 6.49 us |  0.98 |
/// | TestRefType | 541.1 us | 1.98 us | 1.54 us |  1.00 |.
///
/// 1M, Intel Core i9-12900H
/// | Method      | Mean       | Error    | StdDev   | Ratio |
/// |------------ |-----------:|---------:|---------:|------:|
/// | TestValType |   417.8 us |  5.77 us | 14.69 us |  0.39 |
/// | TestRefType | 1,074.9 us | 14.41 us | 12.04 us |  1.00 |.
/// </summary>
public class ValueTypeBenchmark
{
    private const int Count = 1_000_000;

    private static readonly MyRefType[] RefItems = Enumerable
        .Range(0, Count)
        .Select(x => new MyRefType { Field1 = x, Field2 = x + 1 })
        .ToArray();

    private static readonly MyValType[] ValItems = Enumerable
        .Range(0, Count)
        .Select(x => new MyValType { Field1 = x, Field2 = x + 1 })
        .ToArray();

    [Benchmark]
    public int TestValType()
    {
        int sum = 0;

        foreach (var item in ValItems)
        {
            sum += item.Field1 + item.Field2;
        }

        return sum;
    }

    [Benchmark(Baseline = true)]
    public int TestRefType()
    {
        int sum = 0;

        foreach (var item in RefItems)
        {
            sum += item.Field1 + item.Field2;
        }

        return sum;
    }

#pragma warning disable
    public class MyRefType
    {
        public int Field1;
        public int Field2;
    }

    public struct MyValType
    {
        public int Field1;
        public int Field2;
    }
}