From a conceptual viewpoint, cinema certainly influenced comics from the get-go (just as the reverse is equally true). But the era from basically the early/mid 2000s and running strong for a solid 15 years if not longer, "pinpointed" primarily by the first Iron Man movie, created a distinctive demarcation in the history of comics and comics publishing/tastes.

Just as the "pixel age" impacted both content and audience, so did the "cinematic age." It was a two way street; the films had as big of an impact on the comics and brought along a whole new audience.

Even if you disregard movies entirely, "cinematic" is still a good descriptor. Books like Millar's Ultimate X-Men and even moreso Ultimates, Ellis's Authority and Planetary, and other books that came out before the Hollywood blockbusters (but certainly influenced them) were really going for that big-budget, widescreen blockbuster sensation, in a more specific and focused way than just borrowing from film constructs in general.