Given that Michael is risking dying because he is so obsessed with Lucifer, I agree with you guys.
I imagined that while Michael might never have been nice, but at least he used to be a lot better to others before. And then Lucifer, his brother, started his rebellion. I hope there is some more backstory to Michael, I feel something like that would give more depths to Michael, rather him being just an arrogant angel.
I also wondered that Michael is so abusive to Uriel is because he hates him after Uriel commit his crime.
Presuming whatever crime Uriel commited is actually a crime, and it is not just failing to make Solomon an angel. When Uriel talked about Metatron used to be Michael’s confident, Metatron comments that applied to Uriel too. So maybe Michael’s so cruel to Uriel because in his mind Uriel betrayed him and is no better than a demon.
That does not remotely excuse Michael’s actions though.
You know, given that Lucifer rebelled, Uriel did whatever he did, Metatron plans to overthrow Michael, none of the angels care when Michael’s territory is attacked. Would not surprise me if Michael feels he can’t trust anyone and is a jerkass as a result.