It wasn't always followed on Reddit, but downvoting there was supposed to be for comments that don't contribute to the conversation.
Here the guidance is looser -- the docs don't address comments, but do say to "upvote posts that you like."
I've tried contributing to some conversations and sometimes present a different viewpoint in the interest of thought exchange, but this often results in massive downvotes because people disagree. I'm not going to waste my energy contributing to a community that ends up burying my posts because we have different opinions.
That's true on Reddit to, so I'm kind of being tangential to the original question. I guess what I'm saying is that some people might feel like I do and won't engage in any community, be it Reddit or Lemmy, if it's just going to be an echo chamber.
I feel an urge to go play Horizon Zero Dawn now.