I interpreted what NetWallah wrote as assuming the OP might want to do something more than what was posted

Me too. Why skip entries with no emails if you're not going to use the emails?

I could see

my @emails = map { $_->{email} eq '' ? () : $_->{email} } @$data;
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although it might be clearer to do

my @emails = grep $_, map $_->{email}, @$data;
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