This is going to sound overly negative, when I don't necessarily mean it to, because I enjoyed my time with the campaign.
But this experience reminds me heavily of my time with Cyberpunk 2077. Spent a week, completely addicted, by two carrots: the fun addictive nature of the gameplay, and the promise of something more ambitious around the corner. The latter going largely unfulfilled.
And there are similarities between the two games in terms of production & development, but I wouldn't really go down that avenue, because 343 handled the situation in a way that was much more honest, overall.
Thankfully, I think this game will improve on a more drastic scale and more quickly than Cyberpunk 2077. It just may reach it's potential.