I guess the answer is use Taint if you don't know why and don't use Taint if you know.

Taint inst only for Perl, you can turn on taint for back-ends also.

I find that most the time taint wants to error on root paths or things the user can never touch.
This code can save you a few lines, it untaint's Environment paths.

# Clean up the environment.
delete @ENV{qw(IFS CDPATH ENV BASH_ENV)};
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