most probably a problem of fuzzy terminology¹, perldoc talks about "garbage collection":

 Perl uses a fast and simple, reference-based garbage collection system

see perlobj#Two-Phased-Garbage-Collection

But as opposed to mark-and-sweep Perl's runtime approach is very simple an efficient.

OTOH it can't handle circular references.

And even if mark-and-sweep was used, IIRC Python does it and is still very performant. ²

UPDATES:

¹) from perlglossary

       garbage collection
           A misnamed feature--it should be called, "expecting your mo
+ther to
           pick up after you".  Strictly speaking, Perl doesn’t do thi
+s, but
           it relies on a reference-counting mechanism to keep things 
+tidy.
           However, we rarely speak strictly and will often refer to t
+he
           reference-counting scheme as a form of garbage collection. 
+ (If
           it’s any comfort, when your interpreter exits, a "real" gar
+bage
           collector runs to make sure everything is cleaned up if you
+’ve been
           messy with circular references and such.)
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²) more complicated: "While Python uses the traditional reference counting implementation, it also offers a cycle detector that works to detect reference cycles."