Earlier quoted context omitted.
Actually 'find' will also stat each entry no matter what. Many of the standard-tools that most people would intuitively expect to be rather optimized (find, rsync, gzip) are embarrassingly inefficient under the hood and turn belly up when confronted with data of any significant size. That probably stems from the fact that most of the development on these tools took place during a time when 1GB harddrives were "huge"…
But times have changed, and development isn't dead. Why haven't they been updated? The optimizations you imply are often straightforward and well-understood; not major undertakings to implement.
Maybe because listing 8M files is not a common use case, and there just isn't the motivation to update otherwise perfectly working code. It's not an itchy problem.