@Sue313 Yes, you are understanding it correctly. The reasoning is that you wouldn't have received anything anyway if a guest had cancelled when you have a flexible policy. What it doesn't take into account is that just because a host has a flexible policy doesn't mean they normally have guests cancelling like they are because of COVID. I have a moderate policy, so I'm not due back anything, either. But I've never, in over 3 years of hosting, had a guest cancel where I wasn't either due the 50% refund because they cancelled less than 5 days before check-in, or cancelled too close to the reservation date for me to be able to rebook. It isn't as if we normally have guests cancelling all the time just because we don't have a Strict policy, which seems to be the assumption.
So no, it isn't fair. And especially not fair because Airbnb encourages hosts to choose a Moderate or Flexible policy. But then, I never have any expectations of Airbnb behaving fairly towards hosts, because they have proven, over time, that they don't.