I got asked that question during a Sunday School class on Old Testament conceptions of the divine a few years back. I struggled to gather my thoughts quickly and do that Middle School Teacher “Well, actually… it’s very interesting you see…” thing.
But it is a long and interesting history to process how we went from the regional deity of Yahweh to having monotheism to having the middle tier of gods deleted and the lower tier of gods transformed into individual angels with specific names and identities etc.
It’s hard for modern Christians to hear, but we shouldn’t always take the easy route of reading our own modern conceptions of the divine spheres back into texts like Genesis…
Good post here with more of the history behind the concept:
Since they no longer posed a threat to Yahweh, angels began to gain individuality, leading to the explosion of interest in the angelic and demonic worlds in late Second Temple times. The shift to a single-god system led to another late Second Temple split with seeds in Genesis 6 and a full flowering in the Christian New Testament: the lowest divine tier further divided into good angels and bad angels or demons (see, for example, Matt 25:41; Rev 12:7-9). These beings fight not over supremacy in heaven, but rather over the souls of humanity. This final movement established the basic framework shared by Christian and Islamic monotheism—a single, universal god whose rule is contested by demonic figures.