I think the world has at least in many ways changed a lot less between 1920 and today than in the preceding century, or even the preceding few decades. WW1 did a lot to yank the world into modernity: large scale assembly line industry, women working outside of the house, US interventionism, social welfare (the 30's technically, at least in the US), not to mention the entire modern geo-political landscape all happened, v or at least we're accelerated by the war. Obviously they didn't all happen exclusively in the few years of the war itself, however the few decades surrounding it we're certainly a tumultuous time.

It seems like if you were to graph the pace of change, there would be a hump around the First World War. I think the coming of the information age is creating another hump, but at the same time it seems like so far, surprisingly little has changed as a result of it.