Chris,
Here is a copy of the feedback I sent to an Airbnb supervisor when I encountered the same issue and escalated it so I could get a response. By the time the supervisor got back to me a fellow host had provided me with an explanation through the Community Centre. It is included below.
"Thanks so much for the follow up. Since making the request to speak with a supervisor and escalate the issue I was having regarding a blocked booking... I have since discovered the answer to what was going on. I didn't feel I was getting a satisfactory answer or straight forward explanation from the customer service reps I spoke with. It all felt very veiled and deceptive.
A fellow host responded to my post about blocked bookings on the community center forum (or whatever it's official name is). She told me all about the algorithm that Airbnb has begun using to help screen out potentially risky guests. I could not get that precise information from any Airbnb rep.
It’s just that when I got to read the content of the message my potential guest had received regarding being blocked from booking, I was bewildered and disturbed. I didn’t understand why Airbnb would prevent my potential guest from booking with me.
The wording in the blocked booking messaging is done in such a way as to convey that my booking/listing “may be unsafe” and that the guest should choose another place to stay. It then recommends they try a hotel room instead. This gives the impression that there is something very wrong with my listing/booking and a guest should NOT book it, nor will they be able to book it.
I was aware of the shootings and drop-in parties at several Airbnb listings through the news. But I just didn't put it all together. It wasn’t apparent at first reading what was going on. Now I see that this, my first blocked booking, was due to Airbnb's new implementation of these new practices -- precautionary measures to help guard against risky bookings.
I’m sure it is difficult to balance protecting both guests and hosts simultaneously, not offend potential guests, and yet attempt to allow the freedom of choice in bookings, including all the various factors of timing, setting, number of guests, etc.
However, the language really does appear to make the host’s listing appear “unsafe” which really alarmed me.
I see that with this new algorithm in place there will obviously be situations where a potential guest will be blocked that may actually still be a decent, law abiding, respectful citizen/guest that just happens to meet the high risk criteria of the algorithm. In an effort to try to create safer bookings with less chance of risky situations developing, the screening process will inevitably block some legitimate and there is probably no way around that."