[merb]

they can cancel your subscription. because they can always say it is impossible to provide service without said data.

heck they can even rely on other laws to cancel your service any time they want.

in the next years GDPR will change nearly nothing. except that it will kill some smaller businesses.

GDPR is not strongly enforceable, if people think they have a right to something they still need to go to court.

the only thing which might change is that it will be easier to delete accounts and data (which is a good thing).