jointhefediverse.net seems to be a commonly linked resource for directing people to join the Fediverse.
Curiously, it does not list Lemmy under the list of Reddit alternatives. Their GitHub README explains why.
Previous relevant discussion: https://lemmy.ml/post/78808
It’s just a random person that registered a domain. Be the change you want to see and make your own?
I mean, personally I don’t disagree with that random person 😂