"Small is beautiful" -- combined with the principle that each program should do one thing and do it well you the key to improving so many irrationally ambitious software projects.
Aho is going off the cliff here. To me this looks more like a no holds-barred whitewashing than a eulogy. Richard Gabriel (to say nothing of the MIT crowd) was absolutely right, and it's painful to see him so easily dismissed. We should lament C and Unix being so prevalent today, not wear them like a badge of honor.
Complexity today is insane, take Linux for example, but the darn thing works! The original UNIX was the exact opposite of today's major operating systems in a way, which was designed to perform tasks based on the UNIX philosophy. Linux or any other OS today take complexity to levels the creators of UNIX never foresaw and is one of those aspects they wish today wasn't done. But the world itself has changed since the 70s, and so has Linux too, evolved into having thousands of system calls, whereas the original UNIX had 20.