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
The question is more “how many people on Lemmy know about the ml political stance”
Posts like this (https://feddit.org/post/3912054) with 205 comments show that most of the people are usually aware.
For new joiners, there is a post on [email protected] about this.
FWIW: I used join-lemmy.org and found lemmy.ml, submitted my registration, but then checked on Wikipedia and it says lemmy.world is the largest instance, so I wanted to cancel my registration for lemmy.ml (there’s no such feature according to the admin). Anyway, that’s how I ended up here on lemmy.world 😆
Did not notice any of the political leanings until just a few days ago, so it’s definitely not obvious unless you look deeper into things.
You can have multiple accounts on multiple instances. In fact, I recommend it. No need to delete your ml account, just keep it as a backup or curate a different feed on it.