Several lawsuits were filed over airlines’ resistance to providing customers with refunds when either cancelling or substantially changing itineraries early in the Covid-19 pandemic, as required by U.S. law. A class action lawsuit against American Airlines has been resolved in a draw.
In my experience American Airlines was one of the few ‘good guys’ with refunds. The places to focus on are the airlines and online travel agencies which really did act badly against their customers – like United, JetBlue, Air Canada, and online travel agency sites.