@Hugo488 I'm sorry this has happened to you. I've experienced the same thing as a guest, it was quite a hassle.
If the host genuinely canceled your booking (rather than asked you to cancel it), their listing will display an automated review indicating that they canceled a guest, their calendar will be blocked for those dates, and they will have paid a penalty fee. Usually Airbnb gives the guest a full refund plus a credit worth 10% of the room rate to apply to a replacement.
As you've pointed out, this compensation is inadequate for the cost of last minute accommodation during a major event. I hope you had the foresight to obtain travel insurance.