What I'm saying is that, if someone is predicting a certain amount of economic progress for the year 2000 in 1929, then the fact of the Great Depression and WWI

What I'm saying is that, if someone is predicting a certain amount of economic progress for the year 2000 in 1929, then the fact of the Great Depression and WWII will tend to make predictions more optimistic than reality. Those two events caused a huge amount of damage to the world economy and set it back a long way from where it would otherwise have been a few decades later.