I've noticed in the last few months after Google restricted schema review stars in certain cases that another side effect seems to have happened:
If a review "author" is marked up as an Organization, the stars don't seem to appear, even if the schema data validates properly using the Structured Data Testing Tool.
However, in Google's own review guidelines, it says authors can be an Organization:
https://developers.google.com/search/docs/data-types/review-snippet
This scenario is also not mentioned anywhere in their public blog posts, social media discussions, or otherwise regarding the new limitations on schema stars.
Can anyone explain this peculiarity?