[throwaway290]

It's close enough to counting for the purposes of a magazine article like uuids are close enough to being unique for the purposes of programming.

[shkkmo]

The algorithm accuracy scales with the ratio of memory to set size so you don't actually know if it is "close enough" without an estimate of of the set size.

I think the headline is clickbaity and the article makes no effort to justify it's misuse of the wors 'counting'. The subheadline is far more accurate and doesn't use that many more words.