But we aren't talking here about a noisy dog, we are talking about giving the keys to your home to citizens from two nations that in the last month had systematically bombed thousands of buildings, set fire and demolished millions of homes.
Have burnt-down thousands of houses like yours. After systematically ravaging them, and often after murdering all the owners (owners like you), and their entire families.
They --could-- be also really nice people but the tenant can't know it (and would be facing still a risk against their property being vandalized by a third actor, because is hosting Russians). You would be buying tickets for a lottery for housing the worse nightmarish guest in the planet. The best outcome for the tenant would be to receive a few bucks.
The worse would be renting your home to possible arsonists, looters, people that could be hiding stolen properties in your property, or even serial murderers. It just doesn't worth the trouble, specially when there is a high demand and plenty of better candidates.
What I'm trying to say is that Airbnb is not a charity. "All the customers should paid the same because moral" is not how companies work. Some customers are more expensive to the company than other. Some carry a too poor cost/benefits ratio.