The main reasons for me:

1. People are not used to votes being public, because (afaik) it was just not this way on "traditional" social media (there only the operators might have had access)
2. Votes being public affects far more users than posts, because only a small subgroup of all users actually post anything
3. Votes being private is (imo) much more achievable, as they contain the same message each time either "I like" or "I dislike", more information than that is not conveyable in up- and down-vote-buttons

Mastodon is built around individual posters. When you interact with a post, you interact with the author. Lemmy is built around "communities" (discussions forums) and individual threads/topics. Having multiple different servers handle the voting for a single thread makes much less sense.

The obvious problem is that the author/their instance has a vested interest in up/down votes.

To me votes are a way to signal to others if they should bother reading something. I'm not quite sure how that works on Mastodon. I don't think likes influence visibility outside the home instance?

The author is interested in getting their message out. Think about someone trying to sell stuff, for example. They would want to manipulate the visibility/apparent popularity of a post. Such a party would also be most interested in the identities of supporters/detractors.

If you wanted to create psychological profiles, you could create bait messages and observe the reactions. That would be much more effort, but if that is a concern, then that probably isn't good enough.

1. The problem with trad SoMe is that it is monopolistic. That's because these companies "own" the data and gate-keep access. If you want open social media, you must not have a gate-keeper. Which means that you can't have someone who controls access. That's a fundamental trade-off.

2. So what? Should posts be anonymous as long as they are short?

3. No. It's always data+owner. It doesn't matter if the data is only a single bit.

1. Doesn't change the fact that people are used to their votes not being seen by other users
2. Don't know what that has to do with me saying that more people vote than post
3. of course it is easier with always the same one bit information as it is for something that can be one word or 50k words that are basically never the same. Plus the fact that people want the things they post to be seen, but not necessarily their votes

The obvious problem is that the author/their instance has a vested interest in up/down votes.

The author is interested in getting their message out. Think about someone trying to sell stuff, for example. They would want to manipulate the visibility/apparent popularity of a post. Such a party would also be most interested in the identities of supporters/detractors.

That is the same on every social media platform, including Mastodon

I don't think likes influence visibility outside the home instance?

Likes don't affect that at all, boosts or shares or retweets or whatever they are called affect that and are sent to the author and your followers

If you wanted to create psychological profiles, you could create bait messages and observe the reactions. That would be much more effort, but if that is a concern, then that probably isn't good enough.

At the moment this is very easily achievable in the threadiverse. You just sub to a community and you get everything you need from that community. With my proposal this would be much harder to achieve, as you'd only get the information from people interacting with you, or, if we'd shift it to the community actor, you'd have to control the instance of the community. Sure still possible (it always will be) but a lot harder

@bentigorlich@gehirneimer.de I think with public groups this is less of a concern. They're public after all, votes included

In NodeBB votes (of the up variety) are de facto public, only downvotes are hidden.