although the list (list1, list2, list3, list4) is questionable, since it contains bare words which might be interpreteted as subroutine calls
Whether they are subroutine calls or not doesn't matter. It's a list because of the context - the RHS of a list assignment is always a list. The fact the assignment is a list assignment is caused by the LHS being an array.
qw returns a list
No, it doesn't. In Perl, it's not the operation (operator, subroutine, function) that determines whether a list or a scalar is returned - it's the context. It's always the context. qw in scalar context cannot return a list - there are no lists in scalar context.1
in an old release it used to return an array
In which release was that? And what does "returning an array" mean? Could I push on it? Slice from it? Did it have a name? Perhaps you're confused by the fact in earlier releases qw was calculated at run-time (by doing a split), and nowadays qw is calculated at compile time.
You can assign to a list on the left side, provided the list only consists of variables....
...then assign from the array into the three variables $speed, $colour, $animal arranged in a list.
You're contradiction yourself. First you say it assigns to a list, then you say it assigns to a three variables. It's actually the latter that happens.

1Who will be the first one to claim this time there's such a thing as lists in scalar context?

In reply to Re^2: difference between array and list in perl by JavaFan
in thread difference between array and list in perl by manishrathi

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