Hot air ballooning became the symbol of the late 19th century. Man could finally travel through air! Free like a bird! This was the way of a future! Balloons were everywhere.
And then... airplanes happened. Stupid Wright Brothers. Balloons fall out of fashion faster than you can say "hot air".
For example, everyone knows about vile antisemite Charles Lindbergh, the first man to fly solo across the Atlantic on a airplane. He did so in 1927. The first balloon to fly over the Atlantic? Try 1978. It was piloted by Larry Newman, Jew. Three years later Newman and his team became the first to balloon over the Pacific. Obviously, you've never heard of him until now.
So who knows what the future holds for things that are ubiquitous today? Maybe, in a few decades from now, the airplane will be replaced by... well, we don't know. Something powered by hot air?