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.
I don’t think there is a way to remove that. “Karma” is just the sum of upvotes on all of a users’ posts/comments and that info is always accessible.
We could make the decision to not show that value in the front-ends of course but you’ll likely have very different opinions on that and some front-ends will inevitably show karma.
But if it wasn’t available in the API then apps would have to do a fetch of all the users posts to calculate it, possibly discouraging it.