I get where you're coming from, and you're right, but they didn't 'happen'. Secondarmor has a point in that, on the most part, we can't take what we see from these paintings as reality. Italian Renaissance landscape painters even liked to create idyllic, non-existant pastoral landscapes (based on some classical text with a long title that I forgot the name of) in order to heighten things like religious messages. Much of what you see in landscape depictions of the past can't really be labelled as reality, but fantasy, as it's a person's translation and occasional manipulation in order to make more aesthetic compositions. We can't label them as snapshots.

So envision future landscapes all you want; it's just fantasy.

As for the aesthetic of time in the future, that will go into the debate on what aesthetics is, and if it is an innate understanding that is universally shared. If that's the case, then there's no reason for aesthetics to significantly change in the future.