From a historical perspective, the first 50 years saw the development and refinement of toy trains. By 1950, conventional running was pretty solidly established.
The second part of the century refined what already was developed. For instance, in the 50s, there were cool accessories and a lot more motive power choices and in the 90s, command control and even more refinements to track and motive power, and the choice of toy or hi-rail or something in between.
In real railroads, modern steam, 1st gen. diesels and electrics, were all developed and refined in the first 50 years. The second 50 years was just fine-tuning.
Can you see a trend developing here? Although we live in exciting times, most of the big events, both good and bad, occurred during the first half of the century.
e.g.,
1900-1950
WWI and WWII
A bomb and H bomb
jazz, swing
by 1950 live expectancy had dramatically increased
streamliner trains and transatlantic luxury liners
NY subways and other cities
TV, radio, early computers
radar, mass production of cars
road improvements, airplane invented, improved
rockets
jet aircraft
movies
1950-2000
satellites
ICBMs
refinement of IT
Internet
Eisenhower interstate system
drop of railroad tracks by half
nuclear subs and ships
polio vaccine
rock & roll, hip-hop, hard rock
Korea, Vietnam, beginning of terrorism
I did this from memory, but you see that most of the fundamental achievements were made in the first 50 years of the century. I’m sure I left out some things.
In conclusion, we indeed live in exciting times, both good and bad, but arguably, someone born in 1900 might have had more excitement.