I don't think anyone has polls. There is a much higher far-left proportion than on Reddit, as things stand.

Note that Reddit is one unified world, albeit with division by subreddit.

The Threadiverse is not. Some instances have very different communities -- some only permit certain types of users. And not all instances federate with each other, and if your instance doesn't federate with another, you won't see content from those instances.

So, for example, lemmygrad.ml and to a lesser degree lemmy.ml has a bunch of people -- including the lead Lemmy dev -- who are enthusiastic about Stalin and the Soviet Union, pro-authoritarian-left. Hexbear.net is kinda out there too.

Then you've got exploding-heads.com, which I believe is far-right.

Lemmy.world is more-mainstream, but I'd certainly place it left of Reddit on average. It doesn't federate with lemmygrad.ml and hexbear.net or exploding-heads.com.

Beehaw.org is what I'd call far-left, but less in the authoritarian camp, but they've defederated from lemmy.world.

You can see defederations on an instance under "Blocked instances" at /instances. So for example:

https://lemmy.world/instances

Most instances also say something about their policies in the right-hand sidebar.

I think that some of it is also that some people are very vocal about their political views, and I think that some of those are disproportionately in the far-left camp. Like, if someone wants to vent that they think that society would be better off as an anarchy or that private ownership of industry or money or whatever shouldn't exist, I think that those people are gonna be more likely to have strong feelings about and repeatedly post about their point of disagreement than someone saying "I think that things are going pretty well, but I'd like Tweak X and Y".