It’s actually a fairly confused point theologically and Christians tend to draw these pictures in smeared pastels and charcoal sketches as opposed to pen and ink blueprints because it was and is still a developing idea. There’s a whole complicated history where the literary Jesus transformed from prophet to a divine being in his own right to being a literal aspect of god is complex. I consider Christianity to be semi-polytheistic for the same reason that Hinduism is polytheistic unless you consider each of the gods to be an aspect of a single god.
But it’s more meaningfully and directly polytheistic when you considerate the literary aspects of the bible where the vengeful and violent El amalgamated god is transformed into the lawgiver and transactional god and then into the loving caregiver described by Jesus, and they’re all invoked depending on which is best at the moment. Then you can throw in Jesus, and the Holy Spirit which is probably derived at least in part from Ashera (the mother of Yahweh), and you’ve got a pantheon.
Michael, Gabriel, Azrael, and the rest of the powerful angels would be considered demigods in any other religion, as would ideas like saints (including the Marian cults).