But even than, do you think that the defining characteristic of a collectivistic society is... slavery?
No. In that much, I agree with you. But it does seem reasonable that members of a collectivist society are more likely to accept being dealt a worse hand for the good of the nation, which is pretty clearly what that's meant to represent.
Well, I haven't made it because I don't think collectivism is opposed to hierarchy, far from it! I think it is opposed to any form of arbitrary hierarchy, like someone being a slave because he was purchased by someone else. Please note that i'm talking in anthropomorphic terms, as one could say that the workers in a insectoid society are factually very similar to slaves: but that would not be arbitrary, because they are born to fulfill that role and lack the capacity to be something else, while no human in really good at being a slave.
Being purchased may be arbitrary, but the conditions and reasons that a person is put up for sale generally are not. The only cases where it's purely capitalistic tend to be individualistic slavery cases (e.g. indentured servitude contracts) and are both historically unusual and not reflective of entire pops being enslaved, thus not relevant here. Also, keep in mind that the idea that all people are equal is not inherent to collectivism and in fact is a foundational necessity for its antithesis (individualism). An insect born for the slavery is not really distinct, conceptually, from the idea of a person born for slavery. Peasants and serfs have been considered fundamentally different from nobility in many systems of feudalism, and castes are an idea that arose among humans too. Not to mention concepts of inferior or superior race, as those are only really relevant in a xenophobic situation.
Sorry, perhaps I missed the point, then.
Your idea for how a collectivist society should work is only possible if we assume perfect efficiency. Real life (and video games which attempt to emulate it) do not have perfect efficiency. Therefore, social structure is necessary. I agreed with you on what the goal of that structure in a collectivist society would be. My point is that, regardless of what kind of structure is employed (communism has been a popular one in recent centuries) there will be inefficiencies and imperfections whereby the collectivist goal is not achieved. This does not mean that the ethos – the guiding philosophical principle – is not still collectivist.
Why? If Bogdanov is motivated to work not by money, but by the good of the state, it doesn't make sense to pay him more as an incentive to work: he is expected to do that regardless. He would be better cared for, yes, but when boats become needed the care would shift to his buddy.
This is all well and good, but Bogdanov in this situation is a slave. A slave of his own volition, perhaps, for he is a collectivist (and thus his slave acceptance is high; Paradox's mechanic fits the situation) but a slave nonetheless.