I really thought the story of Halo 5 had more to do with oppression.

The Forerunner's oppression of the people they were trying to keep at peace (through the Mantle). Humanity's oppression of the AIs. Locke's oppression of Chief as symbolic for the oppression the UNSC/ONI/generic-military-complex has had on his whole life.

The end of the game was the outcome of those oppressions. The dramatic shift in the status-quo.

"Oppression always leads to revolution." ? It's generic, but it fits a lot of the themes.

I'm not saying that's it, but I just think it is extremely important to consider the whole message behind the AIs in the game, and the fact that they made them (not just Cortana) such large players in the story. I feel get the sense (more than I can put to words right now) that Halo 5 actually had more symbolism and message going for it than a lot of the previous Halo games did.