Yeah, well, even if it is an open source project, what about git? You can't remove an arbitrary commit in the tree. I'd argue discussions about code follow under the same umbrella.
I really thing people are taking this GDPR thing WAY too seriously. They are really only going after the obvious abusers, IMO.
I doubt it. I've read the 66 page standard and I remember something about "records required for business", ie transactions, tax info, etc. I'd argue employee conversations would fall under the same umbrella.