Steam

File support tickets directly with Arrowhead

https://arrowhead.zendesk.com/hc/en-us

File a complaint with your local government body, I believe in Australia it is illegal to break a game after the fact. To substantially change how it runs to hold it hostage.

But even in other jurisdictions, even 1, 000 disgruntled gamers filing small claims against arrowhead would consume an outsized amount of resources to respond to.

Make noise, be disgruntled, don't play the game, file a negative review, create busy work for the perpetrators. They're stealing time and money from you, it's fair to do it to them. But legally