Wrong, wrong, wrong. People who assumed stormy days ahead in geopolitics have found some sunshine instead. Anyone who counted on improving human nature in hopes of improving society has seen those hopes dashed. But, of course, luck comes and goes, deep insight is rare, and extrapolations don't always work. Predictions, in other words, aren't really about the future at all, but about the present.
Some soothsayers look at the time in which they write and figure the future has to be better.
Bellamy's vision of a socially harmonious 2000 was a reaction against the rude industrialization and labor strife of his day. Experts haven't the foggiest. Even the simplest of demographic extrapolations are tricky to get right. But census projections are notoriously inaccurate. In 1964, Hans H. Landsberg of Resources for the Future predicted that the U.S. population would reach 331 million by 2000.