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
Far be it from me to point out this is exactly how reddit started.
The foundational promise of lemmy and the fediverse writ large is freedom from proprietary software and closed-protocols; the kind of people who are going to be interested in seeking out those types of alternatives are going to gravitate toward techy men.
It takes time for new social media sites to fan outward from their initial adopters, that’s just how it goes.