Rand was just an easy and quick way of generating a large sample set.
Can get large sample sets other ways.
Point being made was that general statements such as "... looping macros ... are inherently slow and less efficient." (as compared with filters) are in many cases just not correct, and thus may be unhelpful to contributors seeking help.
Following code was used to generate, as illustrative counter-example, a large set of numbers
If aim is to find the unique values from the resulting dataset, like Excel's RemoveDuplicates tries to do, then filtering is inherently slow and inefficient.
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