I can say that the "host will receive a photo after accepting the booking" is total BS, as the last guest that I accepted (after conversation) did not have a profile picture, nor did I receive a photo of him.
A better way to do this in my opinion is to take the Uber approach: if you're deciding whether to accept someone or not for a property that's NOT a shared living situation, don't share a photo, name, or any other information from the platform while discussing the situation. If it's a shared living situation, then provide the gender. After the request is approved by the host, THEN release the photo and personal information, but still require the potential guest to have a profile picture.