I can confirm your solution for modifying the Config.tjs does in fact work for running the game on macOS 12. For others interested, to run in Safari, go to the "advanced" tab under Safari preferences and click "Show Develop menu". From the Develop menu, click "disable local file restrictions" and it should be good to go.
Edit: I might have spoken too soon. While I can launch the game in the browser, once I get past the "hairy/shave" choice the game advances to the next screen and just stops. Not a hard crash: It loads the background, but no text and the menus are unresponsive. Any suggestions?
Double edit: Apparently it can be ran in Chrome after using the following command in terminal: /Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome --allow-file-access-from-files