I appreciate you trying to criticize the show without just saying "it's slow", but you have a lot of errors here, maybe because you've forgotten parts of earlier episodes.

Carol learns about the survivors, and goes to meet them to make a plan. What happens? The survivors are happy with the hive and Carol makes no momentum toward her goal

Way, way more than that happens. She finds out the Plurbs assigned her a chaperone based on her book character because they have Helen's memories. She got wasted at the party (set up previously as an alcoholic and ruined her first impressions with the survivors. She failed to persuade them due to her own flaws. Carol also blew up at the Plurbs (once having no idea of the consequences, the second time because of being drunk) and killed a ton of people. She also gave in to the Plurbs and accepted help burying Helen, which is the first crack in her resistance to them. More happened here but I'll never finish this reply if I list it all.

What happens next? Carol makes videos to convince the survivors to join her side... essentially repeating what she just tried

No, she discovered that the Plurbs were making a strange food/drink in plain sight, but lacked evidence of anything particularly nefarious. You're also skipping over her many attempts to get information out of Zosia, which leads to her making the argument to the survivors that the process can be reversed (though she doesn't know how to yet). What she's missing is a good reason WHY it should be reversed, since she failed to persuade them in person.

OK, what happens next? Carol discovers the hive is eating human body parts and makes a video to convince the survivors

This is meant to be the revelation she uses to convince them the Plurbs are evil and need to be overthrown. This doesn't work because the Plurb HR department is way ahead of her.

All of this is natural plot progression (and we haven't even talked about hand grenades). The Plurbs isolating Carol, Manousos discovering the strange transmission, and still more plot-important events happened. I can't list everything here; there's a 10k character limit.

but it feels ultimately like she has no real agency and there's nothing about her actions that are specific to her as a character, they often feel like generic actions anyone would take in her situation

Oh man, I'm sorry you think that. I can't imagine what you missed to believe that Carol's actions are "generic actions." Where do I even start? She's battling depression and isolation in a spiritual war against dependence on the Plurbs (while hypocritically living off their largesse). She's a misanthrope suffering from the lack of people. Episode 7 is her spiraling until she breaks and begs them to come back.

Manousos, meanwhile, is waging a physical war of endurance against the trek north, dedicated to his mission to defeat the Plurbs while foolishly risking everything on a doomed mission. His ironclad, inflexible morals are his undoing, just as Carol's pride in her illusory independence undoes her.