Uhm... No, it didn't. In your case, $env was set to the exit status of whoami(1), probably 0.
Yeah so ... does that mean it "didn't work"?
*Geez*

$ perl -e 'my $env = system( qq ( whoami )) ;'
rbc
$ perl -e 'my $env = system( qq ( whoru )) ;'
wrong
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