I’d say it is (was? It’s been ~a year and a half since I used it consistently but I’m guessing it hasn’t changed too much since then) moderately left by US standards but definitely not progressive left - you don’t have to go very far to find thinly-veiled sexism/racism/homophobia, though that might just be because a large portion of the people there are terminally online in a bad way. That being said, there are definitely also communities ranging from conservative to hardcore conservative as well but I actively tried to avoid those so I didn’t really see them in my feeds. The same is true with progressive communities but they tended to drift away from being actually progressive once they got to a certain size.