Comment by larsrc

Junk writing with cherrypicked examples. As mentioned by others, the collapse of the Roman empire was not slow. Blockbuster may have fallen quickly, but it wasn't any more complex than other companies of our time that have risen quickly or fallen slowly.

Complexity can be fragile or it can be stable. A system with redundancies and ways to adapt can be quite complex and yet stable. And many, many simple systems collapse quickly, for instance most start-ups. It's just not as noticeable as a huge system collapsing quickly.