Not sure whether it was different in the beginning, but nowadays, reviews are only displayed after both parties have submitted theirs - or once the 14 day window for submitting reviews has expired.
Yes — this has fortunately been fixed. I still have the problem where if the hosts are really nice but the place isn't great, I don't want to leave a bad review and shut down their operation. As a result, I mostly leave reviews when the stay was amazing in some way.