It apparently requires some kind of proprietary operating environment to function, thus making it compatible with free (as in freedom) computing. You would need either a proprietary library/OS or an open OS but a proprietary piece of vendor hardware to act as the attester.
Technical explainer:
https://github.com/RupertBenWiser/Web-Environment-Integrity/blob/main/explainer.md#how-it-works
It apparently requires some kind of proprietary operating environment to function, thus making it compatible with free (as in freedom) computing. You would need either a proprietary library/OS or an open OS but a proprietary piece of vendor hardware to act as the attester.
Assuming you meant incompatible.