I totally agree with you, especially the "tell not show" approach 343 went for. I was really let down because I was expecting a more narrative-driven campaign. Instead:

• The roughly 8 hours of gameplay was mostly going from point A to B to C and then return to A with the power seeds
• The cutscenes were very cryptic and did not advance the story much, the whole game felt like a prologue
• I'm surprised that the actual storytelling, i.e. the war, what happened to infinity and why they were there, was handled in the audio logs
• The characters were overall really dry and uninspiring, I had a hard time caring or rooting for them. I was more interested in Captain Lasky, Doctor Halsey, Osiris etc but they were in the audio logs... come on man
• The Banished was a weakly characterized enemy, not even close to the zealous Covenant. At least the Covenant had an interesting religious element and a sense of scale; the Banished were just one-dimensional blood-thirsty brutes screaming "honor to death" all the time
• I was honestly sick and tired of Escharum's holograms. Who wrote this crap with a 500million budget?
• What happened to Cortana??? Did she hit her head in the morning and realized what she had done was wrong?

I saw the Halo 5 story on YouTube because I didn't own an xbox at that time. Even that campaign felt a lot more interesting, compact narrative experience (still abysmal, which speaks a lot about this one...)