הקהל את העם האנשים והנשים והטף וגרך אשר בשעריך למען ישמעו
Gather the nation, men and women and children and converts that live among you so that they will hear....
Even if one were to postulate some kind of collective moral sensorium, that our experiences and actions influence others without our or their realizing it (as Reb Yisrael Salanter said- "If someone says Lashon Hara in the Beis Medrash in Vilna, there will be more chillul Shabbos in Paris", or as the Ibn Ezra says by Egla Arufa in Devarim 21,) that would only make sense for contemporaries. Avraham Avinu's words resulted in the suffering of Shibud Mitzrayim, and his merits benefit his descendants through zechus avos, even though we are not responsible for what he did and not control him. The Tzibur affects the yachid and the behavior of a yachid has an effect on the tzibbur, as Rav Freidlander discusses in his Sifsei Chaim in the section Ein Mazal LeYisrael, as does Rav Meir Berman in his Sifsei Daas II on Haazinu. (Rabbi Dovid Gottlieb, writing as Dale Gottlieb, wrote an article on this question many years ago in Tradition. I found the article stimulating but far from comprehensive. If you want to pay for it, it is available here, but you're not allowed to share it.) Famously, the Rambam in Teshuva says that one individual's behavior can tip the balance of the entire world and create consequences for all the members of the tzibur. Even if the mitzva is to Beis Din, that only means that it 's a mitzva on the tzibur. Tzibur and individual are identical. The covenants, and the renewal of covenant, was with כולכם- the people as a whole- Mattan Torah, Nitzavim, and Hakhel. The deeper truth is only the כולכם. I also believe that the כולכם usually applies only to Klal Yisrael, but might to some extent apply to mankind as a whole.
I realize that this extreme postulate would mean that there is no schar or onesh for individuals. That is absurd, but I don't know where to draw the line. If individuals suffer for the behavior of the tzibur as a whole, and vice versa, then the idea of pure personal self-determination is not correct. Maybe individualism and national organicism, or holistic collectivism, are not mutually exclusive; maybe each reality is fully functional, but I can't figure out how that would work. It seems to me that the former contradicts the latter.