Here in 2021 it has been well over 50 years since the first transistor was built.
> The first working device to be built was a point-contact transistor invented in 1947 by American physicists John Bardeen and Walter Brattain while working under William Shockley at Bell Labs. The three shared the 1956 Nobel Prize in Physics for their achievement.
Yup. This whole era from WW2 onwards (the 3rd/4th Industrial Revolution?) will be looked at as covering 1950 to probably the mid 21st century hundreds of years from now.