I think its great they are promoting Lemmy but I think the notes are unneeded. Tell people Lemmy is great, give them a recommended instance to sign up on, and stop selling. They can learn about the rest after theyve gotten their lemmylegs underneath them.
Give them 5 extra paragraphs of caveats and people will think they are more confused than they are. I ended up on squabbles for two months after the reddit exodus because everytime Lemmy was brought up it was with a massive text wall or that one infocomic. Its free, theres no ads, and no one person owns it - thats really all you need to know to get started.
Your question made me realize I had never thought about this at all so I spent some time searching. If I am understanding this article correctly it essentially boils down to the factors that would cause rotational symmetry at a smaller scale ie spinning sand on a plate apply at the galaxy scale as well.