If there is a queue of buyers that look a much better candidates than me, why should you be forced to rent me your home?.
Airbnb can make any policy that they think is good for the company. They aren't a NGO. If you want to use it you need to accept their rules. Period.
Yes, life is unfair. Nobody would keep you from using another platform to rent your house. There is not such thing as the "right" to use the platform.