Taking into account operator precedence in your first example, the 1 is all that's in scalar context. There is nothing to present a list to the assignment operator at all, and each element item to the right of the assignment operator gets its context separately (two thirds of them getting void context).
in reply to Re^4: If you believe in Lists in Scalar Context, Clap your Hands
in thread If you believe in Lists in Scalar Context, Clap your Hands
Likewise taking into account operator precedence in your second example, only @y is in scalar context. The exception that an array in scalar context yields its length is in effect, and that's what $x gets assigned.
No lists are presented to the operators due to comma being lower in precedence than assignment. I don't see how one's thinking about lists even becomes involved with the thinking about the assignment unless someone doesn't know that the comma operator is lower precedence than assignment.
If someone doesn't understand operator precedence, they have bigger issues than just a mental model of lists.
BTW, I've never programmed more than a couple of dozen lines of Python, total. I also think candy-flavored unicorns sound delightful, if a bit dangerous to taste.
Now, if we were dealing with a concept of lazy vs. eager assignment operators or specific atom and list assignment operators (which would need different names and not both be simply '=') instead of context being determined by the left operand of the infix operator, then that'd be another story. That'd be a different language, too, though.