4channers use Normalfag. "Normie" is the sanitized version for Redditors and Youtubers that are too afraid to use the -fag suffix. Same with the "Glowie" meme.
In that case, I think this conversation may be entirely wrong as "normie" is in no way a new term, and it's not fear keeping people from using the suffix/slur so I don't think people would go looking for a safe alternative.
WebText and WebText2 referenced in their papers are corpuses based on Reddit submissions which had a 22% weight in their training model.
https://openwebtext2.readthedocs.io/en/latest/
This is larger than Wikipedia (3% weight) or either of their two book corpuses (8% each).
The only other data included was a filtered set from Common Crawl (weighted 60%).