Omnipotence will skew someone's responses. Being in a situation of extreme stress will skew someone's responses. Being in a completely day-to-day situation will skew someone's responses. Real people don't have a static alignment in the D&D sense or a particular 'true character'. You might have someone who is great to everyone around them and also wants to be, but when a situation of extreme stress descends (for example, something that forces them to choose between two things they value as highly important such as their family and their friends) then it can produce a complete change in behavior.

Or in other words, someone can be LG until the world turns into a post-apocalyptic landscape, at which point they're NE because they're forced to rank things that they previously gave completely equal value and the decisions induce a sort of hardness. And if they gained omnipotence maybe they'd be CG, because the 'L' part of their alignment was always the fear that they could make a mistake they couldn't fix if they took their own path, but with literal omnipotence they know they can always put things back together if they screw it up.

Not to mention things like embracing order and law in order to understand how to slip their bonds and gain true individuality and other such cross-alignment philosophies.