That would be a closed source stack and device dependent solution. You could also use QR codes to trigger URI access which in turn ran arbitrary code on arbitrary devices. That would be an open source stack and device agnostic solution.

NFC can trigger an interrupt to launch code/app, so proximity is sufficient. NFC exists on multiple platforms. QR codes would require launching an app to read the code, it would be faster for the user to launch the automation shortcut directly.

There is also the issue of security. Which platform hardware+software would you entrust to pull the trigger on an automation sequence with physical side-effects?

NFC costs more to set up. QR you can stick on anything easily, forward or share, etc.

Trust? NIH. Something I wrote myself, only available on the local wireless network segment, probably.