the standard location for AAX builds on MacOS is
/Library/Application Support/Avid/Audio/Plug-Ins, which makes sense since this is where Pro Tools is looking for plugins. Unfortunately on macOS 10.15 this location requires admin privileges for writing, so when XCode is trying to copy the plugin there after building it fails with the error
Is there a way to give XCode permission to write there? Otherwise maybe the standard location for the copy step in Projucer should be re-evaluated, since XCode can’t write there anymore.