HostInterface: Disable true color/enable scaled dithering by default

Too many games are broken with it enabled. The number which break with
scaled dithering is much smaller.

src/core/host_interface.cpp

@@ -958,8 +958,8 @@ void HostInterface::SetDefaultSettings(SettingsInterface& si)
   si.SetStringValue("GPU", "Renderer", Settings::GetRendererName(Settings::DEFAULT_GPU_RENDERER));
   si.SetIntValue("GPU", "ResolutionScale", 1);
   si.SetBoolValue("GPU", "UseDebugDevice", false);
-  si.SetBoolValue("GPU", "TrueColor", true);
-  si.SetBoolValue("GPU", "ScaledDithering", false);
+  si.SetBoolValue("GPU", "TrueColor", false);
+  si.SetBoolValue("GPU", "ScaledDithering", true);
   si.SetBoolValue("GPU", "TextureFiltering", false);
   si.SetBoolValue("GPU", "DisableInterlacing", true);
   si.SetBoolValue("GPU", "ForceNTSCTimings", false);

src/duckstation-qt/gpusettingswidget.cpp

@@ -80,11 +80,12 @@ GPUSettingsWidget::GPUSettingsWidget(QtHostInterface* host_interface, QWidget* p
                              "to the hardware backends. This option is usually safe, with most games looking fine at "
                              "higher resolutions. Higher resolutions require a more powerful GPU.");
   dialog->registerWidgetHelp(
-    m_ui.trueColor, "True Color Rendering (24-bit, disables dithering)", "Checked",
+    m_ui.trueColor, "True Color Rendering (24-bit, disables dithering)", "Unchecked",
     "Forces the precision of colours output to the console's framebuffer to use the full 8 bits of precision per "
     "channel. This produces nicer looking gradients at the cost of making some colours look slightly different. "
     "Disabling the option also enables dithering, which makes the transition between colours less sharp by applying a "
-    "pattern around those pixels. Usually safe to leave enabled, and only applies to the hardware renderers.");
+    "pattern around those pixels. Most games are compatible with this option, but there is a number which aren't and "
+    "will have broken effects with it enabled. Only applies to the hardware renderers.");
   dialog->registerWidgetHelp(
     m_ui.scaledDithering, "Scaled Dithering (scale dither pattern to resolution)", "Checked",
     "Scales the dither pattern to the resolution scale of the emulated GPU. This makes the dither pattern much less "