Well, that’s my unpopular opinion 😉
Unlike content in let’s say Facebook, there is a wealth of knowledge in Reddit that is indexed by search engines, covering a plethora of topics. Removing that knowledge will hurt people searching for that info, while hardly affecting Reddit. Erasing all traces of that content removes the opportunity to tell Redditors and visitors alike about what Reddit had done, and where the authors of that useful content had moved.
I already argued this in OP.
Neither the person who contacted you was a real user of that instance, nor their “concern” was legitimate.
Congrats. You got successfully manipulated. And opened yourself up for further future manipulations.