Hi.
The Steam page actually says that you won’t be able to launch the program if your OS version is older than macOS 10.15.
What happens when you attempt to run the demo?
Viewing post in TDSM is now available on Steam! comments
Hey again!
It just says "tdsm-demo.app can not be opened." No clue whatsoever. I have already selected to trust everything from security and privacy so there should not be any problems. I do not know if any other mac users have encountered this. I can send you the screenshots if you want to investigate further