I came across a comment on HN a few weeks ago linking to a different post in this subreddit, but apparently this myth is confirmed and even has a FAQ entry in AskHistorians

https://old.reddit.com/r/AskHistorians/wiki/vfaq#wiki_middle... (Middle Ages, subsection Health and Hygiene)

The other post I cannot find right now was much more detailed than the faq links, but I can’t seem to find it again using HN search