There’s debate over whether changes to the American Airlines Contract of Carriage (the adhesion contract you’re agreeing to when you buy a ticket) matter or not. The airline says they’re not obligated to put you on another airline when they cancel your flight, and won’t reimburse your hotel if you submit a receipt unless they’re legally required to do so.
It’s this system of providing hotel stays I want to touch on for a moment. The airline has been saying that the only way they will cover your hotel is if they provide you with a voucher.