A possible workaround is to set the RadControl.EnableDpiScaling property to false.
static class Program
{
    /// <summary>
    /// The main entry point for the application.
    /// </summary>
    [STAThread]
    static void Main()
    {
        RadControl.EnableDpiScaling = false;

        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        Application.Run(new RadForm1());
    }
}

Another workaround is to mark the application as DPI-aware: https://docs.telerik.com/devtools/winforms/telerik-presentation-framework/dpi-support