IANAL!!!! But I think, yes, there are still implications. GDPR makes no distinction about back end and front end AFAIK, it's just about what data you collect and why/purpose.

But note there are other reasons you can have for collecting data other than consent (something often overlooked) - for example I would guess GitHub would log IP addresses in the back end for a limited time for spam fighting reasons, and I think that would be fine.