New Post: Save grayscaled image as truecolor PSD file

I am currently experiencing some problems when saving images containing only gray colors to truecolor PSD files.
An example image can be found here.
This image has a valid sRGB color profile and is saved with RGB color space. So far so good. But when saving it as a PSD file via Magic.NET the color space is automatically converted to grayscale. This then leads to the sRGB icc profile being invalid. I searched in multiple forums to find out two things:

-First: I am not the only one having problems with this.
-Second: This is by design.

Okay...by design it is then...but there should be a way to force the resulting color space. I then found this post, which explained a lot, but ultimately failed in helping me.

This is my test code:

public static void SavePsd()
{
    string inputImagePath = @"C:\not_so_gray_at_all.jpg";
    string outputImagePath = @"C:\totally_gray_now.psd";
    
    MagickReadSettings readSettings = new MagickReadSettings() { ColorSpace = ImageMagick.ColorSpace.sRGB };
    using (MagickImageCollection collection = new MagickImageCollection())
    using (MagickImage magickImage = new MagickImage(inputImagePath, readSettings))
    {
        // Set format to psd.
        magickImage.Format = MagickFormat.Psd;

        // Do NOT change the color type.
        magickImage.PreserveColorType();
        
        // For better or worse: Change color type, space and profile.
        magickImage.BitDepth(8);
        magickImage.ColorType = ColorType.TrueColor;
        magickImage.ColorSpace = ImageMagick.ColorSpace.sRGB;
        if (magickImage.GetColorProfile().ColorSpace != ImageMagick.ColorSpace.sRGB)
        {
            ColorProfile targetProfile = ColorProfile.SRGB;
            magickImage.AddProfile(targetProfile);
        }

        // Add the image to the collection.
        collection.Add(magickImage);

        // Create psd file.
        if (File.Exists(outputImagePath)) File.Delete(outputImagePath);
        collection.Write(outputImagePath);
    }
}

So I really tried telling Magic.NET to stick with sRGB but to no avail. Am I missing some property or should I use another method? Using the debugger I found out, that the ReadMask and the WriteMask of Magick.NET are both set to 8bit grayscale (here). But trying to override those properties was fruitless.