10 Times The MCU FRUSTRATINGLY Held Back
8. HYDRA's Influence In S.H.I.E.L.D
The Winter Soldier's winding conspiracy plot ended with the entire world finding out that the Nazi-aligning HYDRA had infiltrated the upper-echelons of S.H.I.E.L.D. after WW2, slowly concocting a plan to take over the world from the inside.
It led to the complete destruction of the world's largest security organisation, but it also posed so many possibilities: How would the Avengers operate now they're on their own? Which former allies will turn out to have been double agents this whole time? What other plans did HYDRA have up their sleeve?
Unfortunately, future films weren't really concerned with answering any of those questions, and barely even touched upon the consequences of HYDRA's takeover at all. The next time we hear about them, The Avengers had already mostly mopped them up, fixing the problem offscreen and at the start of Age of Ultron.
It's once again an issue rooted in Marvel's presentation: the reveal is depicted as being this huge, paradigm-shifting discovery, but because future movies fail to properly delve into its consequences on the world both in the present and throughout history, it lacks any real weight. The movie tells you it's a big deal, but doesn't bother showing you why.