There’s some misinformation floating around regarding Lemmy not having a karma system. While many have discovered otherwise, this is for those who may not have.
While it’s not exposed in the Lemmy default user interface, Lemmy does have a fully functional karma system and it is visible in third party clients such as WefWef and Memmy.
Do with that what you will.
With Reddit, though, some subreddits required a minimum amount of karma to post, whereas if you have access to an instance you can post freely.
So it’s more a user rating of “this was good/how have you survived until this point” than a gatekeeping device: you, as a poster, can freely ignore your points and the points of others if you don’t care.