Lemmy.world is reddit with another interface. All the people there are redditbrained to the core, no wonders that instance was born last July when lemmy was invaded by lib redditors. Lemmy.world mods are (sometimes really) reddit mods. (before july, the biggest instance was lemmy.ml that IMO is way better)
The admins are Marxists (you probably know, libs from other instances cry about "tankie redfash admins censoring my poor, totally respectable opinions" all the time)
The userbase itself is a mix of everything, It was one of the only 2 populated instances a few months ago after all.
Anyhow a big chunk of the userbase (I'd say the majority) is left-wing with some of them (me included) being Marxists, or as the average 'worlder calls them: "evil redfash tankies"
Tldr: the instance doesn't censor/shun Marxist and generally left-wing opinions, and I'd say at least half of the userbase is some flavor of left-wing.