Signal also hands over user data if they get a warrent by the goverment, its just that Signal only collects data when the account was created and last active iirc (useless data). Im not saying Proton is perfect but similar with Proton, they can only hand over data they activly collect, so things like payment methods, recovery email, phonenumber.. etc. The case with this climate activist, was they had a recovery email given to proton and thats the data that unmasked them. And as someone said, if they wouldnt comply they would just get raided.