There’s more to reality than meets the eye. So maybe choice operates differently on different levels or dimensions of existence. Perhaps in our earthly reality, which is bound by time and space, choice exists, while in more transcendent realms of existence that are beyond time and and space, choice is irrelevant.
We have learned that the proximity of Olam HaBriah to Ohr Ein Sof results in a state of self-negation (Bittul). The maamer now explains that although this phenomenon is most obviously true in the case of Olam HaBriah d’Klallus (Adam Kadmon), it is equally applicable to Olam HaBria d’Pratis.