>>42 Those decades of CS research don't cover such radical stretches as you might think; nobody thought it was impossible or even impractical to make an incremental realtime garbage collector, only that it was impractical to make one in 1975. There are in fact very few techniques or technologies that weren't possible or available in 1975, that are possible or available today.

Computers haven't fundementally changed in the last 70 years- they still work basically the same way, and are likely to work the same way in another 70 years.

Programmers weren't "dumber" in 1975, but commonplace programming languages certainly were- if only as a matter of practicality. BASIC and C do things today that only a LISP system could do in 1975, and yet they can't do everything a LISP system could do in 1975.