Seems like CMSIS_PACK_ROOT variable gets somehow corrupted (emptied) between VSCode startup and your debug launch. Your log clearly states that the variable has been well registered at extension init with the expected value on OSX.
Do you have the issue directly after starting VSCode, or only after a period of time?
When it happens, are you able to open the "Setup STM32cube Project(s)" editor without having any errors?
