Uriel’s and the Mothers are beings which exist in multiple realities as a single being, any circle in a single reality is only attempting to capture a fraction of them as a being, most of them are outside the circle breaking its line. It’s not just a question of power.
A circle around the Eye would initially focus the reality warping effect of the Eye for a pico second before it ceases to be a circle in shape and function, and becomes a black hole in reality rather quickly. A being of Ethnui’s power level or above might survive it, those who came into existence before our current reality. Everyone else could easily just turn into a bowl of petunias in those circumstances. That’s where power comes into play, just immortals like Mab can be eventually killed by the Eye used by them or on them rather quickly, they exist in a single reality but someone like Uriel or the Mothers can be killed eventually by the Eye because it would at some point eventually suck the entirety of their being into the black hole in reality it’s use creates, but I suspect it would take the user with it. You need the disparity in power level like between Ethnui and Mab for the wielder to survive destruction of the target. Needless to say casual observers wouldn’t survive such an encounter.
