They may try to sue exchanges that let the funds be transferred out, as the addresses where the thieves sent the stolen funds have been published.
There's absolutely no need for a central authority, but as always we need local courts and law can be different in different places where those exchanges are registered.
Screw globalism and screw central authorities.
Having said that, this DeFi stuff is laughable. As if the main use case is to find greater fools or scam people.