UI: Inline macOS 13 check

UI/platform-osx.mm

@@ -133,15 +133,6 @@ void SetAlwaysOnTop(QWidget *window, bool enable)
     window->show();
 }
 
-bool shouldCreateDefaultAudioSource(void)
-{
-    if (@available(macOS 13, *)) {
-        return false;
-    } else {
-        return true;
-    }
-}
-
 bool SetDisplayAffinitySupported(void)
 {
     // Not implemented yet

UI/platform.hpp

@@ -101,7 +101,6 @@ void InstallNSApplicationSubclass();
 void InstallNSThreadLocks();
 void disableColorSpaceConversion(QWidget *window);
 void SetMacOSDarkMode(bool dark);
-bool shouldCreateDefaultAudioSource();
 
 MacPermissionStatus CheckPermissionWithPrompt(MacPermissionType type,
 					      bool prompt_for_permission);

UI/window-basic-main.cpp

@@ -1023,7 +1023,11 @@ void OBSBasic::CreateFirstRunSources()
 	bool hasInputAudio = HasAudioDevices(App()->InputAudioSource());
 
 #ifdef __APPLE__
-	hasDesktopAudio = hasDesktopAudio && shouldCreateDefaultAudioSource();
+	/* On macOS 13 and above, the SCK based audio capture provides a
+	 * better alternative to the device-based audio capture. */
+	if (__builtin_available(macOS 13.0, *)) {
+		hasDesktopAudio = false;
+	}
 #endif
 
 	if (hasDesktopAudio)