Airbnb switched to a "double blind" review system several years go, so you only see the other person's review after you've written your own. If you don't leave a review within two weeks, the other review becomes public and you no longer have the option to leave a review. I did a search to see if there was any press about this, couldn't find much but there's a bit about it here: https://medium.com/airbnb-engineering/building-for-trust-503... "The result was a 7% increase in review rates and a 2% increase in negative reviews."
My reason for not writing a negative review is because before staying at their place we exchanged phone numbers and other things, and now I don't feel comfortable writing a negative review and possibly having a confrontation. YMMV but I avoid writing negative reviews despite the 'double blind' review system.
Always contact them through AirBnB. You should be treating it just like contacting random strangers for sex on Craigslist, potentially dangerous. There's no reason to give a random stranger your personal contact details.
