The right to keep data beyond when a user requests it's deletion is contingent on it being needed for ongoing business requirements like tax and other audit requirements, not for content.

It's not possible under GDPR to automatically license user submitted content via a ToS or something. If you want to keep content beyond when a user clicks a delete button you would need a contract that provides reasonable compensation for licensing that content.

> the data subject withdraws consent on which the processing is based according to point (a) of Article 6(1), or point (a) of Article 9(2), and where there is no other legal ground for the processing

> Processing of personal data revealing racial or ethnic origin, political opinions, religious or philosophical beliefs, or trade union membership, and the processing of genetic data, biometric data for the purpose of uniquely identifying a natural person, data concerning health or data concerning a natural person’s sex life or sexual orientation shall be prohibited.

But perhaps deleting an account + posts does not qualify as revoking consent?

I dunno anything about GDPR, but Reddit would have to be confident about every condition in Article 17. It makes me think these undeletions are a considered decision, not a knee jerk response.