sadly this took more of my time than i wanted it to. Unfortunately not documented well in the download page.
this is dependent on whether you're running on an INTEL mac or an APPLE SILICON mac.
if you're running on intel, download the x64 versions of both the game and the dotnet runtime.
if you're running on apple silicon, make sure you download both the arm64 version for the dotnet runtime, AND the game.
to be clear: on apple silicon, the files should be called arm64, on intel, the files should be called x64. You may have to click the "mirror" button on the vintagestory download page to make sure you download the right version for your architecture.
Then you must run this command:
sudo xattr -d com.apple.quarantine <game-path>
This is what workd for me. the reason why it took so long for me to figure out was because the major download link for macos on the vintagestory download is for intel macs only, unless you click the 'mirror' button. "mirror" typically implies mirrored files from mirrors, not files compiled for different architectures, this is what confused me.
Follow these steps and it should work for apple silicon macs.