There is good and bad, but you certainly must be blind if you think the progress of technology has been relatively stagnant since the introduction of unix. Just a couple things that come to mind:

* The internet (early 90s)

* Wireless networking (early 2000s)

* Highly portable, small, and lightweight computers (early 2010s)

and all the software that supports them. These "follow-up systems" are certainnly better than their predecessors, and there are literally countless more examples (no, everything shouldn't be written in asm and c).