Although Gerard Butler doesn’t explicitly say in his description about where Angel Has Fallen is heading, it’s hard not to think of mistakes made by the Die Hard franchise.
In effect, the Die Hard series arguably became a parody of itself when John McClane had to save an entire country, instead of one building.
By contrast, Butler seems well-aware that the Has Fallen universe cannot keep getting bigger and bigger with each passing film, so they want to scale things back while also ramping up the emotional intensity of the story.
Bruce Willis’ iconic action series (which very clearly provided the DNA for Olympus Has Fallen) gradually increased its scope and scale with every subsequent entry, to the point at which all of the charm from the original Die Hard was lost.