The issue with the action scenes in DOFP is that they lack character. This is why Quicksilvers stands out so much more. We don't know much of anything about Colossus, Blink, Warpath, Sunspot or Bishop even from a personality stand point so why should we or the audience care? Just cause they are X-Men? They are visual fodder and thats it. And aside from Blink and a solid combo from Storm/Mags the fighting is dull and confined. Sunspot just stands there. Bishop does next to nothing, Iceman finally Iceslides so I guess that's cool? But after over a decade of waiting that's all they could do with it? The X2 scenes are far more affective and well choreographed, especially for their time.
Just that little moment in DOFP where Bobby looks at Kitty says so much because we know their past relationship. We need those connections and moments of honest empathy to care more about these guys. If it was Pyro, Quicksilver and Beast getting slaughterd in those last scenes it would have meant more then characters like Bishop, Sunspot etc. I'll never get adding X-Men for the sake of murdering them.
The airport scene in Civil War while not the most tension filled showcases characters in ways never seen through interactions as well as grand spectacle. The ending battle between Stark, Bucky and Cap is personal and flat out brutal. There's build up, betrayal and choreography to match the former. It had all the ingredients for the audience to be invested and there's just far more regarding action and actual character, which is why that series is still on top.