@HomeGrown-HideAways0 What we know for sure is that clicking "no" will restrict the guest's ability to Instant Book listings with the IB setting "only recommended by other hosts."
The guest can still view and request all listings on the platform, including yours. And of course, you may decline those unlikely requests.
Of course, when reviewing the guest it's not enough to simply click the thumbs-down; at the very least, the written text of your review should give some kind of reason that helps other hosts make an informed decision. Otherwise, it's worse than posting no review.