I found a mention of MACOSX_DEPLOYMENT_TARGET in Xcode's Build Setting Reference.
https://developer.apple.com/library/archive/documentation/DeveloperTools/Reference/XcodeBuildSettingRef/1-Build_Setting_Reference/build_setting_ref.html#//apple_ref/doc/uid/TP40003931-CH3-SW129
I created a new Mac app project in Xcode 14.2, and the project has a setting for the macOS deployment target, so I think the MACOSX_DEPLOYMENT_TARGET build setting is still used.
Topic:
App & System Services
SubTopic:
Core OS
Tags: