Right, but that's because of copyright law.
Because none are.
This is literally what the publishers asked for. If they wanted a different way, they're the copyright lobby. They are making all the rules. They can change it.
There are several things to criticise here, including the US’s terrible copyright laws and the publishers involved in that case who care more about in-print than out-of-print books.
But it’s the AI companies that are actively buying up and destroying books at an unprecedented scale, which is an action they’re choosing do to and certainly don’t have to do. Therefore that’s also where the immediate focus and attention needs to be