The troubleshooting guide has a specific point about mac too, so hopefully this helps if none of the solutions Odin provided does. Pasted from
the guide here:
Run the Terminal application (if you’re not sure how, click the magnifying glass in the top right, type Terminal, and select the first result). In the window that appears, paste in the following line (
CHANGE “USER” to your username) and press enter:
sudo chown -v “$USER” ~/.config[/CODE]
This should correct the ownership of a folder that Stardew Valley needs to write under.
You’ll probably be prompted for your password by the above command, and then it’ll output something like /Users/yournamehere/.config. Try running Stardew Valley again, and hopefully it’ll work this time.