> Which telcos don't, except for billing purposes. Yes, they have a legal obligation to collect and store that data for law enforcement, but they are still boun

> Which telcos don't, except for billing purposes. Yes, they have a legal obligation to collect and store that data for law enforcement, but they are still bound by the GDPR for everything else. They're bound by the GDPR no matter what... it's just that having a legal obligation to process data is a legal basis for processing (it'd be silly for it not to be). If you're interested in why they process data, just ask your them. They have to tell you what legal basis they use to process your data.