Hello again, thank you for sharing that info. I'm sorry that the new build didn't work. Yes, the game is available on Mac in Steam and has worked with no issues for hundreds of people. This has to do with how the Steam API is integrated into Unity builds before it is uploaded to Steam for publication. Dexter Stardust is also available on Nintendo Switch, which has a very rigorous review process. No issues there.
However, itch.io is aware of the issues that MacOS users are having with new Unity builds. This is why they encourage the use of the itch.io app for MacOS. It's still DRM free. There is no DRM in itch games as far as I know.
As far as running the Terminal, you can learn about a workaround here: https://discussions.apple.com/thread/7682929
Even so, if you are not able to run the game, and if you prefer not to download and use the itch app (which I totally understand), please request a refund. Then, if you'd like contact me at dexterteamgames@gmail.com and I'll send you a Steam key for free. In the meantime, take care and enjoy your day!