Similar experience here. Had booked a fairly expensive place in the country for my extended family, over a holiday weekend, to celebrate a milestone birthday for my mother. Host cancelled a couple of days out and literally nothing else available anywhere in that region.
After causing a sufficient amount of fuss because of the urgency of it all it eventually got escalated to someone more senior but the result was the same. Best they could do was a refund, no recourse for the host, with the extra salt in the wounds with the parting words of something like "I can provide you no further help today as it's a holiday weekend and I am leaving now and will not return until Tuesday". To this day I still suspect that the host simply got a higher priced offer given it was a popular weekend that had an unseasonably great weather forecast and so they cancelled on us. No effort to find us alternate accomodation. No refund sufficient to cover the costs of doing it ourselves at such late notice. Nothing that came close to addressing the fact multiple families had now wasted their money on plans they couldn't do.
Unfortunately it's not the first time it had happened either. The story has been the same, the only saving grace in the other situations is we'd been able to work out our own Plan B. I'd never use Airbnb again unless I was confident there was a Plan B I could execute on with only an hours notice. That limits its usefulness to out of season and in areas with a multitude of options, or where I am at least ok significantly adjusting my planned location.