Practically, if you're moving enough data through setenv that the memory leaked versus the steady state fluctuation of the program is at all visible, you've got much bigger problems.
And I personally don't use it or would be likely to approve a review that uses it.
But it I were implementing POSIX and had to implement it, I would almost certainly make Sun's choice thinking of it as the least evil given the expected use cases.
> frequency of data
Practically, if you're moving enough data through setenv that the memory leaked versus the steady state fluctuation of the program is at all visible, you've got much bigger problems.