It doesn't make the encryption more random. That doesn't make any sense.

I suspect he meant the encryption key, not the encryption process. Indeed, making the process random wouldn't make any sense.

$;=sub{$/};@;=map{my($a,$b)=($_,$;);$;=sub{$a.$b->()}}
split//,".rekcah lreP rehtona tsuJ";$\=$ ;->();print$/
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