By default, Lemmy allows downvotes globally. However, when a server disables downvoting, it is similar to using a feature that is usually reserved for enterprises and very small, non-federated communities.
If a user prefer to not see downvotes, they can disable it by his favourite client settings, but the rest of the community should not miss this functionality for the pleasure of few users.
This might be a real unpopular opinion but I think the down vote is a broken feature. We do need some kind of vote to help the best stuff rise to the top, thus the up vote. Down vote basically says “I disagree with your opinion but I don’t have a strong enough rebuttal to engage in the discussion to explain why”. A basic agreement doesn’t usually add a lot to the conversation unless the comment itself comes with additional context, a disagreement requires some level of dialog as to explain why. It encourages this bubble hivemind instead of open discussion. Really makes me miss how popular forums were in the mid 2000s.
It doesn’t really stop spam, we have stronger mechanics for that like reporting, moderation and spambot tools. Plus posts without any engagement usually just fall off pretty quickly without reaching a wider audience.
Then you have your trolls who collect down votes. Having a vote score of 1 is way less compelling for a troll than -15.
Edit
4 down votes without discussion, we’ve just proved the point.
Downvote do have a role… It sort of reading the room.
Sometimes the hot take is too hot, sometimes person literally spouting wrong information with confidence of ChatGPT. You don’t always have to engage.
All of this is true in “natural” social media tho once it becomes big enough too many bad faith actors get involved and no consensus can be built