C# Structural List Loop Processing Time Question

public class TransformSystem
{
    private readonly list <Vector3>vectorArray;

    public TransformSystem (int capacity)
    {
        vectorArray=new List<Vector3>(capacity);
    }

    public void MoveObject (ref float x, ref floaty, ref float z)
    {
        for (inti=0;i<vectorArray.Count;i++)
        {
            varvector3 = vectorArray[i];
            vector 3.x+=x;
            vector3.y+=y;
            vector3.z+=z;
            vectorArray[i] = vector3;
        }
    }

    public void MoveObject (ref Vector 3 direction)
    {
        for (inti=0;i<vectorArray.Count;i++)
        {
            varvector=vectorArray[i];

            vector.x + = direction.x;
            vector.x+=direction.y;
            vector.x+=direction.z;
            vectorArray[i] = vector;
        }
    }
}

internal class program
{
    public static void Main (string[]args)
    {
        int count = 50000;
        while (count <500000)
        {
            Console.WriteLine($"===========Count:{count}===========");
            Execute(count);
            count*=2;
        }
    }

    private static void execute (int count)
    {
        Vector3 direction = new Vector3 {x=1,y=1,z=1};

        Stopwatch sw = new Stopwatch();

        sw.Start();
        TransformSystem system=new TransformSystem(count);
        sw.Stop();
        Console.WriteLine("struct initialization finished.Elapped:"+sw.Elapped);
        sw.Reset();

        sw.Start();
        system.MoveObject(ref direction);
        sw.Stop();
        Console.WriteLine("ref structure moved finished.Elapped:"+sw.Elapped);

        sw.Start();
        system.MoveObject(ref direction.x,ref direction.y,ref direction.z);
        sw.Stop();
        Console.WriteLine("ref structure value moved finished.Elapped:"+sw.Elapped);
    }
}