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

There is. Here's one:

>perl -MO=Concise -e"$x = (4,5,6)" 2>&1 | find "list"
5        <@> list sKP ->6
             ^    ^
             |    |
          list    scalar context
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That's why it's clearer to say "an expression cannot return a list in scalar context". In the above example, the list evaluates to the scalar 6.

Since you know better, why do you use such a needlessly confusing sentence?