Obviously the Holidays are of HaShem’s choosing. What conveyed with אֵלֶּּה הֵם מוֹעֲדָי ?
Sforno explains that only when one involves oneself in the activities of holiness are they considered “My Holidays.” However, when takes the opportunity to pursue physical pleasures, then they are your Holidays, about which the prophet decries “Your appointed feasts My soul heats (Yeshiyahu 1,4).