I don’t find that argument convincing.

• lemmy.world has too much influence in the lemmyverse already, IMHO.
• If the privacyguides mods on lemmy are the same as those on reddit roughly a year ago, I wouldn’t recommend their forum. The quality of their guidance was hit & miss, and more than zero of those mods had a habit of using their position to control discourse and push notions that run against individuals’ privacy and safety. Once their subreddit was created, they seemed to gradually become more self-serving.
• lemmy.ml is already the dominant privacy community on lemmy, as you noted. Its existence doesn’t provide choice.