Comment by tremon

Here's the GDPR in one sentence for you: "do not process data from people that haven't consented to that processing".

The rest of the text is about specifying the terms of art processing, data, people, and consent.

> If you weren't doing anything harmful then your preexisting behavior shouldn't become unlawful.

Exactly. Except that you do not get to define harmful, the law does. If you weren't processing any PII, then your preexisting behaviour did not suddenly become unlawful.