Wow, that's surprising, I've been an AirBnB guest about 10 times and generally had a very good experience. I've had 100% response rate and only once had a problem - which was that the host had a problem with the utilities in the flat and had to cancel my booking a few days before. Annoying, but understandable and well communicated.
Perhaps it's worth looking at your photo and description to see if they can be improved, and also filtering your choices based on the host's reputation and description.
Yeah, this is why I've been leaning towards regular hotels more and more. You can see dates of availability, and confirmation is instant. With Expedia, I always have that stress factor of "are they going to say yes or no?" and often times I end up placing several inquiries just to cover my bases.
Does this mean you typically request same or next day bookings? From my experience, most AirBnB hosts are wary of doing anything last second as they typically need to plan ahead to accommodate a guest.
I had great success in Italy with very short notice bookings (a day or two ahead of time). Most of the places we stayed were set up to be full time rentals, which may make that more feasible.
Perhaps it's worth looking at your photo and description to see if they can be improved, and also filtering your choices based on the host's reputation and description.